WO2020238845A1

WO2020238845A1 - Retransmission data sending method, retransmission data receiving method, and device

Info

Publication number: WO2020238845A1
Application number: PCT/CN2020/092073
Authority: WO
Inventors: 淦明; 林伟; 梁丹丹; 杨讯
Original assignee: 华为技术有限公司
Priority date: 2019-05-25
Filing date: 2020-05-25
Publication date: 2020-12-03
Also published as: CN112073146A; EP3968550A1; CN112073146B; EP3968550A4

Abstract

The present application discloses a retransmission data sending method, a retransmission data receiving method, and a related device, belonging to the field of communication technology. In the present solution, a sending end sends a first aggregated media access control protocol data unit (A-MPDU), the first A-MPDU comprising M A-MPDU subframes and M tail bit parts, one tail bit part being located corresponding to one A-MPDU subframe; the sending end determines N MPDUs in the first A-MPDU that need to be retransmitted, the N MPDUs being respectively included in N A-MPDU subframes of the first A-MPDU; the sending end sends a second A-MPDU, the second A-MPDU comprising N A-MPDU subframes and N tail bit parts corresponding to the N A-MPDU subframes, one tail bit part including at least 6 bits, the at least 6 bits having preset values; and a receiving end can directly perform combination decoding or joint decoding on the log likelihood ratio (LLR) of the encoded bits of the retransmitted MPDU and the LLR of the encoded bits of the last incorrectly received MPDU, improving the transmission efficiency and transmission reliability.

Description

Sending method, receiving method and device for retransmission data

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on May 25, 2019, the application number is 201910442763.4, and the application name is "a method for sending, receiving, and device for retransmission of data", all of which are approved The reference is incorporated in this application.

Technical field

This application relates to the field of communication technology, and in particular to a method and device for sending and receiving retransmitted data.

Background technique

In the communication system, due to the time-varying characteristics and multipath fading of the wireless channel, signal transmission will fail. Generally, forward error correction (FEC, Forward Error Correction) coding technology and automatic repeat request (ARQ, Automatic Repeat-reQuest) methods are used for error control. For example, in WLAN (Wireless Local Area Network, wireless local area network), when the access point (Access Point, AP) sends data to the station (Station, STA), if the STA successfully receives the data, the STA will send back an acknowledgement (Acknowledge, ACK) frame; if the STA does not successfully receive data, it will not feed back any frame. If the AP does not receive any feedback, it will retransmit the sent data and perform error control through retransmission.

On the basis of ARQ, in LTE (Long Term Evolution) and other standards, Hybrid ARQ (HARQ, Hybrid Automatic Repeat Request) has been introduced. The receiving end pre-stores the data received for the first time, and when it receives the retransmitted data, it combines the data received for the first time and the retransmitted data, thereby increasing the success rate of decoding. Because HARQ can further increase the success rate of retransmission data reception, the HARQ mechanism is usually used in deep fading areas or edge areas in wireless networks. This mechanism can often make the sender adopt a higher modulation and coding scheme (MCS). , Improve transmission efficiency.

Since retransmission requires a certain buffer to store the data that needs to be combined, no retransmission mechanism has been introduced in the previous 802.11a/g/n/ac/ax standards. In future WLAN systems, such as next-generation WLAN and 802.11be systems, due to the improvement of hardware performance, retransmission technology that can improve transmission reliability and efficiency is likely to be selected as one of the next-generation WiFi standard technologies. Therefore, how to design HARQ adapted to the WLAN system is very important.

Summary of the invention

The embodiments of the present application provide a data retransmission method and device, which can be applied to a WLAN system, can implement HARQ transmission of the WLAN, and improve the reliability of transmission. The technical solution is as follows:

In a first aspect, a method for sending retransmission data is provided for the sending end, the method includes: sending a first A-MPDU, the first A-MPDU includes M A-MPDU subframes and M tail bit parts, A tail bit part corresponds to an A-MPDU subframe, and M is greater than or equal to 1. Determine the N MPDUs that need to be retransmitted in the first A-MPDU, and the N MPDUs are included in the N A-MPDUs of the first A-MPDU. In a subframe; N is greater than or equal to 1, the M is greater than or equal to N; a second A-MPDU is sent, and the second A-MPDU includes N A-MPDU subframes and corresponding to the N A-MPDU subframes N tail bit parts; one tail bit part includes at least 6 bits, and at least 6 bits are a preset value. The preset value is, for example, all zeros.

In a second aspect, a method for receiving retransmitted data is provided for the receiving end, including: receiving a first A-MPDU, the first A-MPDU includes M A-MPDU subframes and M tail bit parts, one The tail bit part corresponds to an A-MPDU subframe, the M is greater than or equal to 1; the second A-MPDU is received, and the second A-MPDU includes N A-MPDU subframes and corresponds to N A-MPDU subframes N tail bit parts of the; one tail bit part includes at least 6 bits, and at least 6 bits are the preset value; N A-MPDU subframes include N MPDUs that need to be retransmitted in the first A-MPDU; N is greater than or equal to 1 , The M is greater than or equal to N; the LLR corresponding to the first transmitted coded bit corresponding to the N A-MPDU subframes in the first A-MPDU and the retransmission corresponding to the N A-MPDU subframes in the second A-MPDU The LLRs of the coded bits are combined or jointly decoded to obtain N A-MPDU subframes.

In a third aspect, a transmitting device is provided, including: a transmitting module, configured to transmit a first A-MPDU, the first A-MPDU including M A-MPDU subframes and M tail bit parts, one The tail bit part corresponds to one of the A-MPDU subframes, the M is greater than or equal to 1; the processing module is used to determine the N MPDUs that need to be retransmitted in the first A-MPDU, and the N MPDUs respectively include In the N A-MPDU subframes of the first A-MPDU; the N is greater than or equal to 1, and the M is greater than or equal to N; the sending module is also used to send a second A-MPDU, the second A -MPDU includes the N A-MPDU subframes and N tail bit parts corresponding to the N A-MPDU subframes; wherein: one tail bit part includes at least 6 bits, and the at least 6 bits are preamble Set value.

In a fourth aspect, a receiving device is provided, including: a receiving module for receiving a first A-MPDU, the first A-MPDU including M A-MPDU subframes and M tail bit parts, one The tail bit part corresponds to one of the A-MPDU subframes, and the M is greater than or equal to 1. The receiving module is also used to receive a second A-MPDU, and the second A-MPDU includes the N A-MPDUs. MPDU subframes and N tail bit parts corresponding to the N A-MPDU subframes; one tail bit part includes at least 6 bits, and the at least 6 bits are preset values; the N A-MPDUs The MPDU subframe contains the N MPDUs that need to be retransmitted in the first A-MPDU; the N is greater than or equal to 1, and the M is greater than or equal to N; a processing module is used for processing N in the first A-MPDU The LLRs of the first transmitted coded bits corresponding to each A-MPDU subframe and the LLRs of the retransmitted coded bits corresponding to the N A-MPDU subframes in the second A-MPDU are combined or decoded to obtain the result The N A-MPDU subframes.

In combination with any of the foregoing aspects, in a possible design, the N A-MPDU subframes in the first A-MPDU correspond to the first-transmission coded bits obtained by BCC encoding by using the first-transmission coding parameter encoding; the second A-MPDU -The N A-MPDU subframes in the MPDU correspond to the retransmission coded bits obtained by performing BCC coding using retransmission coding parameter coding; the retransmission coding parameter is the same as the first transmission coding parameter or has a preset relationship.

With reference to any of the foregoing aspects, in a possible design, one of the tail bits is located at the last at least 6 bits in the one A-MPDU subframe.

With reference to any of the above aspects, in a possible design, one of the A-MPDU subframes includes a padding field, and if the padding field is greater than 0 bytes and less than 4 bytes, the tail bit part is located in the padding field. The last 6 bits in the field are at least.

With reference to any of the foregoing aspects, in a possible design, if the padding field included in the A-MPDU subframe is 0 bytes, the method further includes: additional padding in the padding field of the A-MPDU subframe 4 bytes, the tail bit part is located at least 6 bits of the last 4 bytes of additional padding.

With reference to any of the foregoing aspects, in a possible design, one of the tail bits is located at least 6 bits filled after the one A-MPDU subframe.

With reference to any of the foregoing aspects, in a possible design, the tail bit part includes 6 bits, and the value of the 6 bits is 000000.

With reference to any of the above aspects, in a possible design, the second A-MPDU subframe is carried in a second PPDU, the second PPDU includes a physical layer preamble, and the physical layer preamble includes one of the following: Multiple items: retransmission indication, used to indicate whether the second PPDU includes a retransmitted MPDU, the retransmission indication takes a first value, used to indicate that the second PPDU includes a retransmitted MPDU; modulation and coding scheme Indication, if the modulation and coding scheme indicator is a special value, the special value is used to indicate that the second PPDU includes only retransmitted MPDUs; the retransmission length indicator is used to indicate all the retransmitted MPDUs included in the second PPDU The total length or total duration of the N A-MPDU subframes; the tail bit position indicator is used to indicate the position of the tail bit corresponding to the last A-MPDU subframe in the N A-MPDU subframes .

In a fifth aspect, a sending device is provided for the sending end, comprising: a memory and a processor, the memory is coupled to the processor, the memory is used to store a computer program, the computer program includes program instructions; the processor is used to call The program instructions implement the method described in the first aspect.

In a sixth aspect, a receiving device is provided for the receiving end, including: a memory and a processor, the memory is coupled to the processor, the memory is used to store a computer program, and the computer program includes program instructions; The processor is used to call the program instructions to implement the data transmission method according to any one of the second aspect.

In a seventh aspect, a computer-readable storage medium is provided. The computer-readable storage medium stores a computer program. The computer program contains at least one piece of code. The at least one piece of code can be executed by a computer to control the computer to execute Aspect to the data transmission method of any one of the fourth aspect.

The eighth aspect provides a computer program, when the computer program is executed by a computer, it is used to execute the data transmission method according to any one of the first to fourth aspects.

Optionally, the computer program may be stored in whole or in part on a storage medium that is packaged with the processor, or may be stored in part or in a memory that is not packaged with the processor.

In a ninth aspect, a chip is provided, including a processor, configured to call and execute instructions stored in the memory from a memory, so that a communication device installed with the chip executes the method of any of the above aspects.

In a tenth aspect, the embodiments of the present application also provide another chip. The chip may be a part of the receiving end or the transmitting end. The chip includes: an input interface, an output interface, and a circuit. The input interface, the output interface, and the The circuits are connected by internal connection paths, and the circuits are used to implement any of the above methods.

On the eleventh aspect, another chip is provided, including: an input interface, an output interface, a processor, and optionally, a memory. The input interface, the output interface, the processor, and the memory pass through internal The connection path is connected, the processor is used to execute the code in the memory, and when the code is executed, the processor is used to execute any of the above methods.

In a twelfth aspect, a device is provided to implement the method of any one of the above aspects.

In a thirteenth aspect, a communication system is provided, including: a sending end and at least one receiving end, the sending end includes the sending device as described in the third aspect, and the receiving end includes the receiving end as described in the fourth aspect. Device; or, the transmitting end includes the transmitting device according to the fifth aspect, and the receiving end includes the receiving device according to the sixth aspect.

The technical solution of this application realizes MPDU retransmission based on the A-MPDU structure, can support retransmission in WLAN, further improves the transmission reliability and transmission efficiency of the WLAN system, and allows the receiving end to directly encode the retransmission code The combined decoding or joint decoding of the LLR of the bit and the LLR of the first transmitted coded bit reduces the complexity of the receiving end, saves the decoding time of the receiving end, and improves the transmission efficiency.

Description of the drawings

FIG. 1 is a schematic diagram of an application scenario provided by an embodiment of the present application;

FIG. 2 is a schematic diagram of a frame structure of an A-MPDU provided by an embodiment of the present application;

3 is a schematic flowchart of a method for retransmitting data provided by an embodiment of the present application;

4 is a schematic diagram of information bits and coded bits of an A-MPDU provided by an embodiment of the present application;

FIG. 5 is a schematic flowchart of a method for sending retransmitted data according to an embodiment of the present application;

Figure 6a is a schematic structural diagram of a first A-MPDU provided by an embodiment of the present application;

FIG. 6b is a schematic structural diagram of a second A-MPDU provided by an embodiment of the present application;

Figure 6c is a schematic structural diagram of another second A-MPDU provided by an embodiment of the present application;

FIG. 6d is a schematic structural diagram of yet another second A-MPDU provided by an embodiment of the present application;

FIG. 7a is a schematic structural diagram of another first A-MPDU provided by an embodiment of the present application;

FIG. 7b is a schematic structural diagram of another second A-MPDU provided by an embodiment of the present application;

FIG. 7c is a schematic structural diagram of another second A-MPDU provided by an embodiment of the present application;

Figure 7d is a schematic structural diagram of yet another second A-MPDU provided by an embodiment of the present application;

FIG. 8 is a schematic flowchart of another method for receiving retransmitted data according to an embodiment of the present application;

FIG. 9 is a schematic flowchart of another method for sending retransmitted data provided by an embodiment of the present application;

FIG. 10 is a schematic flowchart of another method for receiving retransmitted data according to an embodiment of the present application;

FIG. 11 is a schematic flowchart of another method for sending retransmitted data provided by an embodiment of the present application;

Figure 12a is a schematic structural diagram of yet another first A-MPDU provided by an embodiment of the present application;

FIG. 12b is a schematic structural diagram of yet another second A-MPDU provided by an embodiment of the present application;

FIG. 12c is a schematic structural diagram of yet another second A-MPDU provided by an embodiment of the present application;

FIG. 12d is a schematic structural diagram of another second A-MPDU provided by an embodiment of the present application;

FIG. 13 is a schematic flowchart of another method for receiving retransmitted data according to an embodiment of the present application;

FIG. 14 is a schematic flowchart of another method for sending retransmission data provided by an embodiment of the present application;

15 is a schematic flowchart of another method for receiving retransmitted data according to an embodiment of the present application;

FIG. 16 is a schematic structural diagram of a sending device provided by an embodiment of the present application;

FIG. 17 is a schematic structural diagram of a receiving device provided by an embodiment of the present application;

FIG. 18 is a schematic structural diagram of another sending device provided by an embodiment of the present application;

FIG. 19 is a schematic structural diagram of another receiving device provided by an embodiment of the present application.

Detailed ways

In order to make the purpose, technical solutions, and advantages of the present application clearer, the following further describes the embodiments of the present application in detail with reference to the accompanying drawings.

In the wireless communication system, due to the time-varying characteristics and multipath fading of the wireless channel, the signal transmission will fail. Therefore, forward error correction (FEC, Forward Error Correction) coding technology and automatic repeat request (ARQ, Automatic Repeat) are usually used. -reQuest) and other methods for error control.

Retransmission technology refers to the sending end re-sending data that has not been successfully received or correctly received by the receiving end. Retransmission techniques may include ARQ and HARQ. Compared with ARQ, HARQ can further increase the success rate of retransmission data reception. The HAQR technology in LTE generally includes two implementation modes: Chase Combining (CC) and Incremental Redundancy (IR).

Chasing combination, also known as soft merger. During the retransmission of the CC type, the sender will retransmit the same coded bits as the previously erroneously transmitted coded bits. The retransmitted coded bits include information bits and check bits. The receiving end combines the retransmitted coded bits with the previously received first transmitted coded bits. Here, the LLR (Log-Likelihood Ratio) of the coded bits transmitted incorrectly last time is combined with the LLR of the coded bits currently received, and then the combined LLR value is decoded.

In the process of incremental redundancy retransmission, the sender will retransmit the retransmission coded bits, which are different from the previously transmitted coded bits, such as the sender retransmits additional parity bits or retransmits new ones. The generated check bits, or the sender retransmits information bits and part of the check bits, or retransmits another part of the encoded codeword, where the retransmitted encoded bits may have different redundancy versions (Redundant Version). The receiving end jointly decodes the original information and the additional received retransmission coded bit information. Since the number of bits retransmitted by HAQR IR is small, HARQ IR is more efficient than HARQ CC, but the coding codebook needs to be redesigned and the complexity is higher.

In a wireless communication system, such as a cellular communication system supporting LTE or 5G, the sender sends a single data packet, and the single data packet includes only one data sub-packet, and multiple data sub-packets are not aggregated. If the data packet is sent incorrectly, received incorrectly or unsuccessfully received, the sender first encodes the data packet to be retransmitted, then scrambles the encoded bits, and then performs constellation point mapping modulation, upload frequency, etc., and finally passes The transmitting antenna sends to the receiving end. After receiving the signal, the receiving end correspondingly performs constellation point demapping and descrambling in sequence, and combines the LLR of each coded bit after descrambling with the LLR of each coded bit received last time for combined decoding or joint interpretation. Code, decode the information bits of the data packet. In the case where data packets aggregate multiple data sub-packets or data frames aggregate multiple data sub-frames, how to retransmit some of the multiple data sub-frames to improve transmission reliability and transmission efficiency is still unclear. Technical problems solved. Therefore, the embodiments of the present application provide a method for sending retransmitted data, a method for receiving, and a device, so that the receiving end can perform combined decoding and joint decoding on the LLR of the retransmitted coded bit and the LLR of the previously transmitted coded bit. Improve the efficiency of retransmission, thereby improving the transmission efficiency and reliability of the wireless communication system.

It should be noted that the solution of the embodiment of the present application is applicable to various wireless communication systems, for example, a cellular communication system, a wireless local area network (WALN) communication system, etc. Among them, the cellular communication system can support multiple communication protocols, such as the 5G NR communication standard protocol, or the future cellular communication protocol; the WLAN communication system can also support multiple WLAN communication protocols, such as the Institute of Electrical and Electronics Engineers (Institute of Electrical and Electronics Engineers). Electrical and Electronics Engineers, IEEE) 802.11ax protocol, and the next-generation protocol of IEEE802.11ax protocol or a next-generation protocol.

The solution of the embodiment of the present application can be applied to the communication between the sending end and the receiving end in the aforementioned communication system. Among them, the sending end and the receiving end may be wireless communication devices or chips that support wireless communication, such as base stations, terminals, etc. in a cellular communication system, or chips in base station terminals, or access points and chips in a WLAN communication system. Site, or access point and chip in the site, etc. For example, terminals and stations can also be called user terminals, user devices, access devices, subscriber stations, subscriber units, mobile stations, user agents, user equipment, or other names. Among them, user terminals can include various wireless communication functions. Hand-held devices, vehicle-mounted devices, wearable devices, computing devices or other processing devices connected to wireless modems, as well as various forms of user equipment (User Equipment, referred to as UE), mobile station (Mobile station, referred to as MS), terminal (terminal) ), terminal equipment (Terminal Equipment), portable communication equipment, handsets, portable computing equipment, entertainment equipment, gaming equipment or systems, global positioning system equipment or any other suitable equipment configured for network communication via wireless media, etc. . Base stations or access points may include various forms of macro base stations, micro base stations, relay stations, and wireless access points.

For ease of description, the embodiment of the present application takes a WLAN as an example for description. A WLAN can include multiple basic service sets (Basic Service Set, BSS). The basic service set shown in Figure 1 includes access point sites (AP) and non-access point sites (None access). point station, Non-AP STA), where an access point type station is usually referred to as an access point, that is, AP, and a non-access point type station is usually abbreviated as a station, that is, STA. Each basic service set can include one AP and multiple STAs associated with the AP. An access point is a device with a wireless transceiver function that can provide services for the site. The station is a device with wireless transceiver function, which can access the wireless local area network based on the access point. Therefore, in this application scenario, the sending end may be an access point or a station, and the receiving end may also be an access point or a station. That is to say, the method of the embodiment of the present application can be used for communication between an access point and an access point, communication between an access point and a station, and can also be applied for communication between a station and a station.

In WLAN, AP and STA transfer data, control signaling, or management signaling through a media intervention control protocol data unit (MAC Protocol Data Unit, MPDU). The MPDU usually includes a frame header, a frame body (Frame Body), and a frame check sequence (Frame Check Sequence, FCS). Among them, the frame body is used to carry the data, management information or control information passed down by the upper layer. For some specific types of MPDUs, the frame body may not exist, such as confirmation frames. FCS is used to verify whether the MPDU is transmitted correctly. The frame header can include a frame control (Frame Control) field, a duration or identification (Duration/ID) field, an address information field, a sequence control (Sequence Control) field, a quality of service control (Quality of Service Control, QoS Control) field, and high throughput At least one field in the rate control (High Throughput Control, HT Control) field. The explanation of each field may refer to the IEEE 802.11 protocol, which is not repeated in the embodiment of the present application.

In order to improve WLAN performance, frame aggregation technology is currently used in the MAC layer to aggregate multiple MPDUs into an aggregate MPDU (Aggregated MPDU, A-MPDU). A-MPDU aggregates multiple MPDUs together and sends them through a unified physical layer preamble, which effectively reduces the overhead caused by competing channels and physical layer preamble, and improves transmission efficiency. Figure 2 is a schematic diagram of the structure of the A-MPDU in the IEEE 802.11 standard. As shown in Figure 2, the A-MPDU includes n A-MPDU subframes, and n is an integer greater than or equal to 1. Optionally, referring to FIG. 2, the A-MPDU may also include an end of frame (EOF) pad field located after the n A-MPDU subframes. Among them, each A-MPDU subframe includes an MPDU delimiter (delimiter) and an MPDU. Optionally, the A-MPDU subframe may also include a padding field. Among them, the MPDU separator is used to separate multiple aggregated MPDUs.

Optionally, the MPDU delimiter includes at least one of the EOF field, the reserved bit (reserved) field, the MPDU length (MPDU length) field, the Cyclic Redundancy Code (CRC) field, and the delimiter signature (delimiter signature) field. A field. The embodiment of the present application does not limit the content contained in the MPDU separator and the sequence of each field.

In particular, for an A-MPDU that contains only one separator and one MPDU, the EOF field in the MPDU separator is set to 1, which is also called Single MPDU (S-MPDU, Single Media Intervention Control Protocol Data Unit). For MPDUs and S-MPDUs, the 802.11 standard adopts a simple Ack confirmation frame for reply mechanism, which indicates whether the MPDU or S-MPDU is successfully received by sending the confirmation frame; and for A-MPDUs that include at least two MPDUs, Use Block Ack (including variants of block confirmation frames, such as basic block confirmation frames, compressed block confirmation frames, multi-service type block confirmation frames, Multi-STA Block Ack frames, etc.) Reply. Among them, the block confirmation frame includes a bitmap. A bit in the bitmap corresponds to an MPDU and is used to indicate whether the corresponding MPDU in the A-MPDU is received correctly, where 1 indicates that the corresponding MPDU is received correctly, and 0 indicates the corresponding The MPDU was received incorrectly. If each MPDU in the aggregated frame A-MPDU is not received correctly or is not received, the STA does not feedback the confirmation information.

For ease of understanding, the embodiment of the present application first describes the general data sending and data receiving process. Due to the different order of scrambling and decoding, the process of data sending and data receiving can be divided into two situations. The first process is encoding first, then scrambling; the second process: scrambling first, then encoding.

An implementation of the first process: The sender generates a MAC frame at the Media access control (MAC) layer, such as an A-MPDU frame; the MAC frame includes multiple information bits, and the MAC frame is passed to the physical layer ( Physical layer, PHY), in the PHY layer, add a physical layer preamble, encapsulate it into a physical layer protocol data unit (PPDU) or physical layer data packet, encode, scramble, and constellation point mapping for the PPDU After that, it is sent out via the antenna. After receiving the signal, the receiving end correspondingly performs constellation point demapping, descrambling, and decoding in the PHY layer to obtain the PHY layer PPDU, and decapsulates the PPDU to obtain the MAC frame, thereby obtaining information bits.

An implementation of the second process: the sender generates a MAC frame of the Media access control (MAC) layer, such as an A-MPDU frame; the MAC frame includes multiple information bits; the PHY layer can encapsulate the MAC frame into After the PPDU, it is scrambled, then encoded, and sent out via the antenna. Correspondingly, the receiving end decodes the received signal and then descrambles to obtain the PHY layer data unit, and then decapsulates to obtain the MAC frame.

It should be noted that the sending end and the receiving end may also include other baseband processing and radio frequency processing. The embodiments of this application will not be described in detail. In the data receiving and sending process, there are many types of encoding and decoding that can be used. For the convenience of description, the embodiment of the present application takes Binary Convolutional Code (BCC) as an example for description. Convolutional code is a type of channel coding technology, and belongs to an error-correcting code in the telecommunication field. Compared with block codes, convolutional codes maintain the memory property of the channel. The convolutional code encoder is essentially a finite state linear shift register. The linear shift register stores the input information bits, and the register is connected to the algebraic operation unit according to certain rules. In this way, the information bits are sequentially input to the register in order, and the arithmetic unit performs algebraic operations by receiving the information bits input to the register, and outputs the result of the operation as coded bits. In the embodiments of the present application, the initial input value in the register of the convolutional code encoder is called the initial state, and the end input value in the register of the convolutional code encoder is called the end state. One of the encoding methods currently used in WiFi is BCC encoding. The initial state of the BCC encoder is 6 bits all 0s, and the end state is 6 all 0s padded tail bits to end. The code rates are 1/2, 2/3, 3/4, and 5/6, and the BCC coding generator polynomials with a code rate of 1/2 are g ₀ =133 ₈ and g ₁ =171 ₈ . Other code rates of 2/3, 3/4 and 5/6 are periodically punctured with coded bits generated by BCC of code rate 1/2. Each encoded bit output by the BCC encoder is related to the 6-bit status value stored in the 6 registers at this time and the 1-bit information input at this time; each time the BCC encoder outputs an encoded bit, the 6-bit status stored in the 6 registers is Shift right, the leftmost bit state is replaced by the 1-bit information input at this time, and the rightmost bit state is removed and no longer exists.

Starting from WiFi's 802.11n, in order to improve efficiency, the transmission of data packets has evolved to the A-MPDU transmission method in which multiple MPDUs are aggregated. Since the physical layer does not identify each A-MPDU subframe in the A-MPDU, It just takes the entire A-MPDU as a whole and adds 6 padding bits of all 0s after the A-MPDU, and then performs BCC channel coding. For the convenience of description in the embodiments of this application, remember that the first A-MPDU is the previously transmitted A-MPDU, and the second A-MPDU is the retransmitted A-MPDU; where the first A-MPDU includes M A-MPDU subframes After the first A-MPDU is sent out, it is determined by the received confirmation information that the N A-MPDU subframes include N MPDUs that need to be retransmitted, which are called N retransmitted MPDUs. The second A-MPDU includes all The N A-MPDU subframes. Optionally, the second A-MPDU may also include other MPDUs, which are non-retransmitted MPDUs. The scrambling code sequence used in the previous transmission of the MPDU is called the first transmission scrambling code sequence, the coding parameter used in the previous transmission is called the first transmission coding parameter, and the coded bits corresponding to the N A-MPDU subframes during the previous transmission are called the first transmission Coded bits; the scrambling code sequence used for retransmission of N MPDUs is called the retransmission scrambling code sequence, the parameters used for retransmission of N MPDUs are called retransmission coding parameters, and the N A-MPDU subframes correspond to the retransmission The coded bits are called retransmission coded bits. The first A-MPDU is carried in the data field of the first PPDU, and the second A-MPDU is carried in the data field of the second PPDU. The previous transmission can be the previous transmission of the retransmission or the first transmission. The retransmitted MPDU includes a single retransmitted MPDU and/or at least two consecutive MPDUs to be retransmitted. A single retransmitted MPDU can be recorded as the first retransmitted MPDU, and at least two consecutive retransmitted MPDUs can be recorded as the second retransmission. MPDU. The solution in the embodiment of the present application is not only suitable for multiple MPDUs that need to be retransmitted, but at the same time, it is suitable for a situation where one MPDU needs to be retransmitted. It is worth noting that the retransmitted MPDU here is used to perform HARQ operations for the receiver. If the retransmitted MPDU is only used for ARQ operations, it does not fall within the scope of the retransmitted MPDU here.

Embodiment 1: Figure 3 shows a schematic flow chart of an interactive method for retransmitting data provided by an embodiment of the present application, and the interactive flow includes:

S101: The sending end sends a first aggregated media intervention control protocol data unit A-MPDU, where the first A-MPDU includes M A-MPDU subframes, and the first A-MPDU adopts BCC encoding.

S102: Receive confirmation information fed back by the receiving end to the first A-MPDU, and determine according to the confirmation information that there are N A-MPDU subframes in the first A-MPDU that have failed to be sent, where N is greater than or equal to 1 and less than or equal to M.

The sending end determines that the N MPDUs included in the N A-MPDU subframes in the first A-MPDU need to be retransmitted, which is called N retransmitted MPDUs. Optionally, the M A-MPDU subframes may also include other A-MPDU subframes, and MPDUs in other A-MPDU subframes do not need to be retransmitted.

The sender can determine which MPDUs of the previously transmitted A-MPDUs need to be retransmitted based on multiple methods. For example, it can be based on the confirmation information sent by the receiving end, or it can be combined with its own business requirements, or it can be determined which MPDUs previously transmitted need to be retransmitted according to the confirmation information sent by the receiving end and its actual situation.

One way: the sender determines which MPDUs need to be retransmitted based on the confirmation information fed back by the receiver. Therefore, optionally, the confirmation information fed back by the receiving end is used to indicate to the sending end which MPDUs of the previously transmitted A-MPDUs are received successfully. For example, the receiving end can inform the sending end through negative acknowledgment (NACK) information, or the bitmap in the Block Ack frame, or the bitmap in the Multi-STA Block Ack frame Which MPDUs were not received successfully or failed.

Optionally, the MPDU that needs to be retransmitted may be the MPDU that was not successfully received by the receiver (reception failure) in the previous transmission, and the MPDU that does not need to be retransmitted may be the MPDU that was successfully received (received successfully) by the receiver in the previous transmission. Or there is no need to retransmit the incorrectly received MPDU, for example, the effective time of the MPDU is over.

S103: The sending end sends a second A-MPDU, the N A-MPDU subframes included in the second A-MPDU, and the N A-MPDU subframes adopt retransmission coding parameters to perform BCC coding.

For the convenience of description, the coding parameter adopted by the first A-MPDU is called the first transmission coding parameter, where the retransmission coding parameter is the same as the first transmission coding parameter or there is a preset relationship; the N A-MPDUs are retransmitted The N initial states for performing BCC encoding on MPDU subframes are respectively the same as the N initial states for transmitting the N A-MPDU subframes for BCC encoding first.

Optionally, the N end states of retransmitting the N A-MPDU subframes for BCC encoding are the same as the N end states of first transmitting the N A-MPDU subframes for BCC encoding; wherein, The initial state is the initial input value of the BCC encoding register, and the end state is the ending input value of the BCC encoding register.

Optionally, the second A-MPDU may also include a newly transmitted MPDU (non-retransmitted MPDU), and the coding parameter used to encode the A-MPDU subframe corresponding to the newly transmitted MPDU may be the same as the retransmission coding parameter The same or different. The periodic scrambling code sequence used for the new transmission may be the same as or different from the periodic scrambling code sequence used in the retransmission, which is not limited in the embodiment of the present application. Optionally, the sequence of the N A-MPDU subframes in the second A-MPDU is the same as the sequence of the N A-MPDU subframes in the first A-MPDU subframe. The N A-MPDU subframes may be located at a preset position in the second A-MPDU, for example, at a start position, a middle position or an end position. The preset location may be specified by the protocol or designated by the AP, or the AP and the STA may negotiate and decide. Since A-MPDU may contain one or more of management frame, control frame, and data frame, if only the data frame supports HARQ transmission, then the retransmitted MPDU only needs to be placed in the preset position of all data frames or all other A- Before the MPDU subframe, such as the start position, the middle position or the end position. The preset location may be specified by the protocol or designated by the AP, or the AP and the STA may negotiate and decide. In another implementation manner, the A-MPDU subframe corresponding to the retransmitted MPDU is placed after the preamble of the existing PPDU and before the service field. Optionally, the PPDU also includes physical layer padding bits and packet expansion fields.

In the retransmission, the initial state of BCC encoding the retransmitted A-MPDU subframe, that is, the initial input value of the encoding register for BCC encoding of the retransmitted A-MPDU subframe, called the retransmission initial state, and the retransmission A -The end state of the BCC encoding of the MPDU subframe, that is, the end input value of the encoding register for BCC encoding of the retransmitted A-MPDU subframe, which is called the retransmission end state.

Since when N A-MPDU subframes are retransmitted, the initial retransmission state of each A-MPDU subframe is the same as the initial state of the first transmission, and the retransmission coding parameters and the first transmission coding parameters are the same or have a preset relationship, so that The receiving end can combine or jointly decode the LLR of the first transmitted coded bit and the LLR of the retransmitted coded bit, which reduces the complexity of the receiving end, saves the decoding time of the receiving end, and improves the efficiency of retransmission. It also supports HARQ transmission of A-MPDU structure in WLAN.

Optionally, the coding parameters (the retransmission coding parameters and the first transmission coding parameters) include: a code rate, and a generator matrix corresponding to the code rate; optionally, a puncturing mode is also included. The retransmission coding parameters are the same as the first transmission coding parameters. It can refer to: the code rate, and the corresponding generator matrix of the code rate is the same. Optionally, if the coding parameters include the puncturing mode, the retransmission and the first transmission are the same. The hole pattern is also the same. The preset relationship between the retransmission coding parameters and the first transmission coding parameters refers to: the code rate, and the corresponding multinomial matrix of the code rate is the same. If the coding parameters include the puncturing mode, the retransmission and the first transmission puncturing mode There is a preset relationship, the coded bits obtained by retransmitting the puncturing mode and the coded bits obtained by the first transmission of the puncturing mode can be combined into the coded bits obtained after the new puncturing mode.

The retransmitted MPDU may be a continuous MPDU or a non-continuous MPDU. Therefore, the N retransmitted MPDUs may include at least one of the following:

The first type of retransmission MPDU: is a single retransmission MPDU. This single retransmitted MPDU is not adjacent or continuous to any other retransmitted MPDU in the first A-MPDU subframe.

The second type of retransmitted MPDU: at least two consecutive retransmitted MPDUs; at least two consecutive retransmitted MPDUs refer to the retransmissions with adjacent MPDUs or adjacent sequence numbers in the first A-MPDU. To transmit MPDUs, for example, the first A-MPDU includes MPDU 1, MPDU 2, MPDU 3, MPDU 4, and MPDU 5, and MPDU 2 and MPDU 3 are adjacent, then MPDU 2 and MPDU 3 can be called continuous MPDUs; if MPDU 2 and MPDU 3 are not If it is successfully received or transmitted incorrectly by the receiving end, it needs to be retransmitted, and other MPDUs are received correctly and do not need to be retransmitted, then MPDU 2 and MPDU 3 can be called continuous MPDUs to be retransmitted.

It is understandable that the N retransmitted MPDUs may include at least one of the above two retransmitted MPDUs, and of course, may also include multiple retransmitted MPDUs of the first type and/or multiple retransmitted MPDUs of the second type, for example: N The two retransmitted MPDUs are at least one single first MPDU, and at least two consecutive first MPDUs. For example, the first A-MPDU includes MPDU 1, MPDU 2, MPDU 3, MPDU 4, and MPDU 5, and MPDU 2 and MPDU 3 are adjacent, then MPDU 2 and MPDU 3 can be called continuous MPDUs; if MPDU 2 and MPDU 3 are not receiving end Successful reception or transmission error requires retransmission, MPDU5 is not continuous with MPDU2 and MPDU3, and is not successfully received, MPDU1 and MPDU4 are received correctly and do not need to be retransmitted, then MPDU2 and MPDU3 can be called continuous retransmission MPDU (the second type of retransmission MPDU), MPDU5 is a separate retransmission MPDU (the first type of retransmission MPDU).

In the embodiment of the present application, the ways to make the N retransmission initial states the same as the N first transmission initial states include but are not limited to the following:

The first implementation manner: M A-MPDU subframes of the first A-MPDU correspond to M tail bit parts; each tail bit part includes at least 6 bits, and at least 6 bits are preset values. For example, the value of the tail bits of the at least 6 bits is all 0s, and the preset value may also be other values, which are agreed upon by a protocol or negotiated between AP and STA. Optionally, the M tail bits may be added after the corresponding M A-MDPU subframes; in addition to the last A-MPDU subframe, the M-1 tail bits may also be included in the corresponding In the first M-1 A-MPDU subframes, and located in the last few bits of the padding field of the corresponding (M-1) A-MPDU subframes; the last bit part of the last A-MPDU subframe is the entire A-MPDU subframe -The tail bit part of the MPDU frame shall not be changed. Since in the existing WiFi protocol, the BCC encoder includes 6-bit registers, the tail bit part can be 6 bits, and its value is all 0. It is understandable. Of course, the BCC encoder can also include more than 6-bit registers. The tail bit part can also be greater than 6 bits, and of course the preset value can also be other values other than all zeros.

For the first transmission process (encode first, then scramble): the initial state of the retransmission of N A-MPDU subframes is the tail bit part, and the end state is also the tail bit part. The initial state is the tail bit part first, and the end state is also the tail bit part.

For the second transmission process (scramble first, then encode): the initial state of retransmission of N A-MPDU subframes is the scrambled tail bit part set to the preset value, and the end state is also set to preset The scrambled tail bit part of the value; in one example, retransmission coding parameters are used for N A-MPDU subframes in M A-MPDU subframes, and BCC coding is performed to obtain retransmission coded bits, including: A-MPDU subframes and the N tail bits corresponding to the N A-MPDU subframes are scrambled by the retransmission scrambling code sequence to obtain the scrambled N A-MPDU subframes and the scrambled N tail bit parts; set the scrambled N tail bit parts to the preset value, and use retransmission for the scrambled N A-MPDU subframes and the N tail bit parts set to the preset value The encoding parameters are encoded to obtain retransmission coded bits; wherein the initial state of the retransmission is the scrambled tail bit portion set to a preset value, and the retransmission end state is the scrambled tail bit portion set to the preset value. What needs to be said is that in order to ensure that HARQ can still be performed after first scrambling and then encoding, the retransmission scrambling code sequence needs to be the same as the first transmission scrambling code sequence, that is, the same periodic scrambler sequence (depending on the scrambler seed) , And the first bit or the nth bit of the sequence that scrambles the N A-MPDU subframes during retransmission and the first bit or the nth bit of the sequence that scrambles the N A-MPDU subframes during the previous transmission the same. In an example, the scrambling code sequence is a periodic 127-bit sequence.

It should be noted that for the first embodiment, both the first A-MPDU and the second A-MPDU need to be added as the tail bit part of the preset value, and the transmission process of the first A-MPDU and the second A-MPDU Are the same.

In the first implementation manner, since the initial state and end state of the BCC encoder encoding N A-MPDU subframes during retransmission are the same as the initial state of encoding N A-MPDU subframes by BCC encoding during previous transmissions The state and the end state are respectively the same, so that the receiving end can directly combine or jointly decode the LLR of the first transmitted coded bit and the LLR of the retransmitted coded bit, which improves the transmission efficiency.

The second implementation mode: It is not necessary to add tail bits to the end of each A-MPDU subframe in the A-MPDU, but to use N retransmission MPDUs before and after the correct reception (or without retransmission) A-MPDU subframes The information bits of the frame are used as the initial state and the end state of the BCC encoder. For the first transmission process (encode first, then scramble): When retransmitting the MPDU, the initial state of the retransmission is in the first A-MPDU, adjacent to the retransmitted MPDU and located before the retransmitted MPDU At least the last 6 bits of the A-MPDU subframe where the correctly received MPDU is located, the retransmission end state is in the first A-MPDU, adjacent to the retransmitted MPDU, and located after the retransmitted MPDU At least the first 6 bits of the A-MPDU subframe where the correctly received MPDU is located;

For the second transmission process (scramble first, then encode): when retransmitting the MPDU, the initial state of the retransmission is the first A-MPDU, which is adjacent to the retransmitted MPDU and is located before the retransmitted MPDU. At least the last 6 bits of the scrambled A-MPDU subframe in which the MPDU is retransmitted, the retransmission end state is in the first A-MPDU, adjacent to the retransmitted MPDU and located after the retransmitted MPDU At least the first 6 bits of the scrambled A-MPDU subframe where the non-retransmitted MPDU is located; and the retransmitted scrambling code sequence is the same as the first transmitted scrambling code sequence, that is, the same periodic scrambler sequence (depending on the scrambling code Device seed), and the first bit or the nth bit of the sequence scrambling the N A-MPDU subframes during retransmission and the first bit or the first bit of the sequence scrambling the N A-MPDU subframes during the previous transmission. The nth bit is the same. In an example, the scrambling code sequence is a periodic 127-bit sequence.

It should be noted that, in the second embodiment, the N retransmitted MPDUs include at least one retransmitted MPDU of the first type and at least one retransmitted MPDU of the second type, or, the N retransmitted MPDUs include multiple first retransmitted MPDUs. A retransmitted MPDU, or N retransmitted MPDUs include multiple second retransmitted MPDUs, the retransmitted coded bit obtained by retransmission coding is not a complete BCC coded bit, but is composed of multiple parts.

For the second implementation mode, there is no need to add additional tail bits. Instead, the information bits of the A-MPDU subframes corresponding to the MPDUs that are correctly received (or do not need to be retransmitted) before and after the N retransmission MPDUs are used or have been added. The scrambled information bits are used as the initial state and end state of the BCC encoder, so there is no need to modify the structure of the existing A-MPDU, which has better compatibility.

The third implementation mode: During the previous transmission, the sender buffers the first A-MPDU encoded bits, which include the first transmitted encoded bits after N A-MPDU subframes are encoded. In the retransmission, the sender can directly Obtain the buffered N A-MPDU subframes' first-transmission coded bits and use them as retransmission coded bits, so that there is no need to re-encode the N A-MPDU subframes by BCC coding, which reduces the complexity of the sender and improves The efficiency of the receiving end. The third implementation manner needs to be combined with the first or second implementation manner to make the initial state during BCC encoding the same, and it is optional, so that the end state is also the same.

For the first implementation, there are multiple ways to add tail bits:

1) PHY filling method: add a tail bit part after the end of each A-MPDU subframe, the tail bit part includes 6 bits or more tail bits, the value is a preset value, such as all 0s.

2) MAC filling method: In the existing A-MPDU structure, as shown in Figure 2, each A-MPDU subframe contains MPDU spacers, MPDUs and padding. The padding bytes are 0 to 3 bytes. The bit value of is not specified. Except that the last A-MPDU subframe does not need to be an integer multiple of 4 bytes, other A-MPDU subframes need to be 4 bytes integers, which are mainly used by the receiver to quickly find the MPDU delimiter through the 4-byte sliding window to avoid When some MPDUs are wrong, other correctly received MPDUs can still be found. Specific MAC filling methods include at least:

I. If the A-MPDU subframe needs to be filled with 0 bytes, 4 additional bytes are filled in the A-MPDU subframe, and at least the last 6 bits of the additional 4 bytes can be used as the tail bit part. At least 6 bits of tail bits must be set to a preset value, such as all 0s. Other padding bits can also be set to preset values.

II. If the A-MPDU subframe needs to be filled with 1 to 3 bytes, the A-MPDU subframe does not need to be filled with extra bytes, and the last 6 bits of the existing 1 to 3 bytes are used as the tail bits Part, the tail bit part of at least 6 bits needs to be set to a preset value, such as all 0s. Other padding bits can also be set to preset values.

After the second A-MPDU carrying N A-MPDU subframes is assembled at the MAC layer, it is delivered to the PHY layer. At the PHY layer, a physical layer preamble is added later to form a PPDU.

To support HARQ transmission, optionally, the physical layer preamble of the PPDU includes one or more of the following:

Optionally, retransmit the instruction information. The retransmission indication information is used to indicate whether a retransmission MPDU is carried in the PPDU, or in other words, the retransmission indication information is used to indicate whether the retransmission indication information in this PPDU needs to correspond to the previous erroneous reception. MPDU performs HARQ and LLR combined decoding or joint decoding. There can be one or multiple retransmission MPDUs. For example, the MPDU retransmission indication takes a first value to indicate that the PPDU includes a retransmitted MPDU, and the MPDU retransmission indication takes a second value to indicate that the PPDU does not include a retransmitted PPDU. The MPDU that needs to be retransmitted can be an unsuccessfully received MPDU in the previous transmission for HARQ transmission. The receiving end will perform LLR combined decoding or joint decoding on the retransmitted MPDU and the last corresponding failed MPDU. The transmitted MPDU (or called the initial transmission MPDU) can be the MPDU successfully received in the previous transmission, and also includes the retransmitted MPDU used for ARQ transmission. Although the MPDU is retransmitted, the receiver does not need to retransmit MPDU carries on corresponding HARQ reception processing. Optionally, the receiving end that receives the retransmission indication can determine whether it is necessary to perform HARQ LLR combined decoding or joint decoding for the retransmitted MPDU in this PPDU and the corresponding MPDU received in error.

Optionally, the physical layer preamble or preamble of the PPDU includes a modulation and coding scheme indicator. If the modulation and coding scheme indicator is a special value, it indicates that the PPDU includes only retransmitted MPDUs, here There can be one or more MPDUs to be retransmitted. If the MPDU contained in the A-MPDU is a retransmitted MPDU, it can be indicated by using a special data modulation and coding scheme in the physical layer preamble. The special modulation and coding scheme indication takes a special value, such as an unused value Or an undefined value. Currently, the modulation and coding scheme in 802.11ax is represented by 4 bits. Currently, modulation and coding schemes 0 to 11 have been used, and modulation and coding schemes 12 to 15 are unused. Therefore, the special value can be 12-15.

Optionally, the preamble of the PPDU includes: a retransmission length indicator, which is used to indicate the total length of the N A-MPDU subframes of the retransmitted MPDU included in the PPDU; the total length is in byte units. In an embodiment, the total length may also be a virtual total length, and the transmission time is equal to the virtual total length divided by a fixed rate, such as the minimum rate supported by WIFI, 6Mbps. That is, in an example, the virtual total length may be based on The transmission duration and the length calculated from the minimum rate supported by wifi, or the retransmission length indication indicates the total duration of N A-MPDU subframes for retransmission of the MPDU. In the subsequent embodiments, the total length can refer to the actual length or the virtual total length.

For the first implementation manner, optionally, the preamble of the PPDU includes: a tail bit position indicator, which is used to indicate the tail bit of the last A-MPDU subframe in one or more A-MPDU subframes of the retransmitted MPDU position. Optionally, the number of bits included in the tail bit can be negotiated and agreed upon by the protocol, for example, 6 bits. The tail bit position indicator can only indicate the position of the first bit (first bit) or the last bit (last bit) among the 6 bits. ), the tail bit position refers to the position of the tail bit part in the second A-MPDU. Carrying the tail bit position indicator in the physical layer preamble can facilitate the receiving end to quickly find the end state of the BCC encoder, that is, the tail bit.

For the second implementation manner, optionally, the preamble of the PPDU includes: an end state position indicator, which is used to indicate each first type of retransmitted MPDU and/or each second type of retransmitted MPDU including N retransmitted MPDUs The end state position of the A-MPDU subframe corresponding to the MPDU is transmitted. For the case where N retransmitted MPDUs include only one retransmitted MPDU of the first type or only the second retransmitted MPDU, the end state position indication may only indicate the last one of the A-MPDU subframes of one or more retransmitted MPDUs The end state position of the A-MPDU subframe.

Optionally, the preamble of the PPDU may not include the retransmission indication. For the first implementation manner, it may be indicated by the retransmission length, or the tail bit position indication multiplexing indicates whether the PPDU includes a retransmission MPDU. For example, the retransmission length indicator can take a special value. For example, a value of 0 indicates that the PPDU does not include retransmitted MPDUs. If the retransmission length indicator takes other values, it indicates that the PPDU includes retransmitted MPDUs, and the value can indicate that it includes The total length of the A-MPDU subframe of the retransmitted MPDU. For another example, the tail bit position indicator can have a special value. For example, a value of 0 indicates that the PPDU does not include a retransmitted MPDU, and the tail bit position indicator takes other values to indicate that the PPDU includes a retransmitted MPDU, and the value can indicate that the PPDU includes a retransmitted MPDU. The position of the tail bit part corresponding to the last A-MPDU subframe in the A-MPDU subframe for transmitting the MPDU. For the second implementation manner, the retransmission length indicator or the end status position indicator multiplexing can be used to indicate whether the PPDU includes a retransmission MPDU. The principle is similar to the first implementation manner and will not be repeated here.

Optionally, the preamble of the PPDU includes: a scrambler seed indication, which is used to indicate the scrambler seed used for scrambling the retransmitted MPDU.

Optionally, performing BCC encoding on the N A-MPDU subframes during retransmission includes but is not limited to the following two methods:

1) For HARQ CC, use the same coding parameters (including the code rate, and the corresponding generator matrix of the code rate) for a single MPDU to be retransmitted or A-MPDU subframes corresponding to at least two consecutive MPDUs to be retransmitted, and Optional punching mode) for BCC encoding. The retransmission coding parameter is the same as the first transmission coding parameter, which means that the code rate used in the retransmission and the previous transmission is the same. The code rate corresponding to the generator matrix is the same, and optionally, the puncturing mode used is the same.

BCC coding parameters (for example, retransmission coding parameters and first transmission coding parameters) include a code rate, a matrix of multiple generations, and optionally, a puncturing mode. Generally speaking, for the standard protocol of the application product, one code rate corresponds to one generator multinomial matrix, and the optional puncturing mode is also included. In academic discussions, each bit rate can correspond to different generating multiple matrices and puncturing modes.

2) For HARQ IR, perform BCC coding with the same parameters on the A-MPDU subframes corresponding to a single MPDU to be retransmitted or at least two consecutive MPDUs to be retransmitted, including the code rate and its corresponding generation matrix. Then the coded bits are periodically punctured according to another puncturing mode different from the previously transmitted puncturing mode to generate punctured coded bits. The puncturing mode used in retransmission is different from the puncturing mode used in the previous transmission, and there is a preset relationship. The coded bits generated by the puncturing mode of the retransmission and the puncturing mode of the previous transmission can be combined as another new puncturing Pattern or coded bits generated without puncturing. Therefore, the preset relationship between the retransmission coding parameters and the first transmission coding parameters refers to: the code rate used in the retransmission and the previous transmission, the corresponding multinomial matrix of the code rate is the same, and the puncturing mode used in the retransmission is the same as the previous transmission. There is a preset relationship in the punching mode used.

S104: The receiving end performs combined decoding or joint decoding on the maximum likelihood ratio LLRs of the retransmitted coded bits and the first transmitted coded bits to obtain the N A-MPDU subframes.

The receiving end can obtain the initial state and the end state of the BCC encoding based on multiple methods, and the specific method can refer to the subsequent embodiments.

In a simple retransmission method, if the receiving end feeds back one of the MPDU reception errors, the transmitting end usually retransmits the MPDU and encodes the A-MPDU subframe corresponding to the MPDU. However, even if the sender uses the same code length and bit rate BCC for the A-MPDU subframe of the retransmitted MPDU, the position of the A-MPDU subframe corresponding to the retransmitted MPDU in the previously transmitted A-MPDU is and The position of the A-MPDU transmitted this time is not the same, resulting in a difference between the initial state and the end state of the two BCC encodings during the previous transmission and retransmission of the A-MPDU subframe corresponding to the MPDU. Therefore, the receiving end cannot perform LLR combined decoding or joint decoding on the retransmitted coded bits and the previously received coded bits. For example, assuming that the adopted BCC code rate is 1/2, since BCC coding is non-block coding, there is no fixed code length, after coding, it is usually regarded as a BCC codeword whose overall initial state and end state are all 0s. As shown in Figure 4, in the previous transmission, the first A-MPDU includes A-MPDU subframes 1 to 5, corresponding to MPDUs 1 to 5, respectively. If MPDU 2 is received incorrectly, A-MPDU subframe 2 includes information bits 16 to 28 Bits, a total of 13 bits. During the previous transmission, the BCC coded bits corresponding to A-MPDU subframe 23 have 19 bits. The initial state of this part of the BCC coded bits is the previous A-MPDU subframe 1 adjacent to A-MPDU subframe 2. The last 6 bits of the A-MPDU, that is, bit 10 to bit 15, the end state is the last 6 bits of A-MPDU subframe 2, that is, bit 23 to bit 28. During retransmission, if the sender re-BCC encodes MPDU 2, and if there is no other MPDU to be transmitted at this time, the initial state and end state of the BCC encoder are all 0s. Since the initial state and the end state of the BCC encoding for the two transmissions are different, the encoded bits of the A-MPDU subframe 2 in the two transmissions are different, so the receiving end cannot retransmit the encoded bits with the previous transmission. The coded bits are LLR combined decoding or joint decoding.

The solution of the embodiment of the present application enables the receiving end to combine and decode the LLR of the retransmitted coded bits and the LLR of the first transmitted coded bits, and realize the HARQ transmission supporting the A-MPDU structure in the WLAN. Improve the transmission efficiency and transmission reliability of WLAN.

The following provides detailed descriptions of several implementation manners of this application in conjunction with more drawings. Among them, Example 2 to Example 5 are described in detail for the first implementation (adding tail bit part) in Example 1, and Example 2 and Example 3 are for the first process, and Example 4 and Example Five is for the second process. The sixth to the ninth embodiment are described in detail for the second implementation in the first embodiment (without adding the tail bit part), and the sixth and seventh embodiments are for the first process, and the eighth and ninth embodiments are for the first process. Two processes. The tenth embodiment introduces retransmission signaling.

Embodiment 2 Regarding the foregoing first process (that is, the transmitting end performs encoding and then scrambling, and correspondingly, the receiving end performs descrambling and then decoding), a detailed description of the embodiment of this application provides a transmission of retransmitted data. method. Since the information bits are first encoded and then scrambled, the scrambling code sequence can be the same or different for each A-MPDU transmission.

FIG. 5 shows a schematic flowchart of a method for sending retransmission data according to an embodiment of the present application, and the method includes:

S201: Send a first A-MPDU, where the first A-MPDU includes M A-MPDU subframes and M tail bit parts, and one tail bit part corresponds to one A-MPDU subframe. M is greater than or equal to 1;

Each A-MPDU subframe includes one MPDU, and each A-MPDU subframe corresponds to a tail bit portion, the tail bit portion includes at least 6 bits, and the value is a preset value, for example, all 0s. A tail bit part may be located after an A-MPDU subframe, or may be located at the last few bits in the A-MPDU subframe. It is understandable that the value of the tail bit part may also be other values. The value of the tail bit part may be agreed upon by a protocol, or may be determined through negotiation between the AP and the STA, which is not specifically limited in the embodiment of the present application.

In an example, 6 or more preset tail bits are newly added after each A-MPDU subframe, such as all 0s, except for the last A-MPDU subframe, because the entire A-MPDU will add 6 bits at the end All 0 tail bits.

The method for adding tail bits includes but is not limited to: PHY filling method and MAC filling method. Using the PHY filling method, a tail bit part is located after the corresponding A-MPDU subframe; using the MAC filling method, a tail bit is the last few bits in an A-MPDU subframe.

1) PHY filling method: add 6 or more tail bits after the end of each A-MPDU subframe, the value is a preset value, such as all 0s.

2) MAC filling method: In the existing A-MPDU structure, as shown in Figure 2, each A-MPDU subframe contains an MPDU spacer, MPDU and a filling field. The number of bytes in the filling field is 0~3 Byte, the bit value of padding is not specified. Except that the last A-MPDU subframe does not need to be an integer multiple of 4 bytes, other A-MPDU subframes need to be 4 bytes integers, which are mainly used by the receiver to quickly find the MPDU delimiter through the 4-byte sliding window. So that when some MPDUs are wrong, other correctly received MPDUs can still be found. The MAC filling method may include the following implementation modes:

I. When the A-MPDU subframe needs to be filled with 0 bytes, the A-MPDU subframe needs to be filled with additional 4 bytes, and the last 6 bits of the additional 4 bytes can be used as the tail bit part. The tail bit part of the bit needs to be set to a preset value, such as all 0s. The other padding bits in the additional 4 bytes can also be set to preset values. In other words, the padding field of the A-MPDU subframe does not exist, but the A-MPDU subframe includes 4 bytes of extra padding, and the last 6 bits of the 4 bytes of extra padding are used as the tail bit part, which is set as a preset value.

II. When the A-MPDU subframe needs to be filled with 1 to 3 bytes, the A-MPDU subframe does not need to be filled with extra bytes, and at least the last 6 bits of the filled 1 to 3 bytes are used as the tail bits. The tail bits of at least 6 bits need to be set to a preset value, such as all 0s. Other padding bits can also be set to preset values.

The transmitting end performs BCC encoding on the first A-MPDU subframe using the first-pass encoding parameter to obtain the encoded bits, which includes the first-pass encoding bit after performing BCC encoding on the N A-MPDU subframes using the first-pass encoding parameter.

The first A-MPDU is included in the data field of the first PPDU. Optionally, the transmitting end may transmit the first PPDU in a single user SU (Single User) mode transmission, or may transmit the first PPDU in a multi-user MU (Multiple User) mode, where the multi-user mode is divided into OFDMA transmission. MU-MIMO mode, or a mixed mode of OFDMA and MU-MIMO.

S202: Determine N MPDUs that need to be retransmitted in the first A-MPDU, where the N MPDUs are respectively included in the N A-MPDU subframes of the first A-MPDU; the N is greater than or equal to 1, so Said M is greater than or equal to N;

The receiving end that receives the first A-MPDU sends confirmation feedback information to the sending end based on its actual reception situation to inform the sending end which MPDUs in the first A-MPDU transmitted this time have not been successfully received. The sender confirms which MPDUs to retransmit by combining the confirmation feedback frame with its own sending situation. Unsuccessful reception can also be referred to as reception failure, or transmission failure. Optionally, before step S202, the method further includes that the receiving end feeds back confirmation information to the transmitting end to indicate that the N MPDUs have not been successfully received.

This application does not limit the receiving end to send the confirmation feedback method. The receiving end can confirm the NACK information by negative, or block the bitmap in the Block Ack frame, or the bitmap in the Multi-STA Block Ack frame tells the sender which The MPDU is not received successfully or fails, but its corresponding traditional preamble is received correctly or can identify the sender and receiver of all MPDUs, that is, inform the sender which MPDUs can be retransmitted based on HARQ rules. NACK can be a single frame or a part of Multi-STA Block Ack, which is different from the current acknowledgement frame and non-reply. It informs the sender that all MPDUs sent this time have not been received correctly, and all MPDUs can be one or There are multiple, but the corresponding physical layer preamble is received correctly or can identify the sender and receiver of all MPDUs transmitted this time.

For example, as shown in Figure 6a, MPDU2 in A-MPDU subframe 2 in the first A-MPDU subframe and MPDU2 in A-MPDU subframe 3 are not successfully received. The confirmation feedback frame carries indication information to indicate the A -MPDU2 and MPDU3 in the MPDU were not successfully received. For example, if the indication information is a bitmap, including 5 bits, the first to fifth bits correspond to the MPDUs in the A-MDPU subframes 1 to 5 respectively. In an example, a value of 0 indicates that the reception was not successful. A value of 1 indicates successful reception, and the 5-bit value may be 10011; of course, a value of 1 may also indicate unsuccessful reception, and a value of 0 may indicate successful reception. The embodiment of the present application is not limited.

For the situation where all MPDUs included in the A-MPDU are not successfully received, there may be multiple feedback modes. The first feedback method: a non-reply method can be used, that is, the receiving end does not feed back confirmation information to the sending end, and the receiving end can know that all MPDUs have not been successfully received. The second feedback method, which is different from the first feedback method, uses NACK information as confirmation feedback to inform the receiving end that all MPDUs included in the A-MPDU sent this time have not been successfully received. Optionally, the NACK information may be individually encapsulated into a frame or may be a part of a Multi-STA Block Ack frame to inform that all MPDUs included in the A-MPDU sent this time have not been successfully received.

In step S202, the sender determines that the N MPDUs in the first A-MDPU need to be retransmitted. Optionally, the first A-MPDU also includes other MPDUs, and other MPDUs do not need to be retransmitted. Similar to the foregoing embodiment, the N retransmitted MPDUs may also include the first retransmitted MPDU and/or the second retransmitted MPDU.

S203: Send a second A-MPDU, where the second A-MPDU includes the N A-MPDU subframes and N tail bit parts corresponding to the N A-MPDU subframes; one tail The bit part includes at least 6 bits, and the at least 6 bits are preset values; the N A-MPDU subframes include N retransmitted MPDUs.

After confirming that N MPDUs need to be retransmitted, the sender retransmits the N MPDUs in S203; optionally, the second A-MPDU may include other MPDUs in addition to the N retransmitted MPDUs. Other MPDUs are Newly transmitted MPDU (non-retransmitted MPDU). The N A-MPDU subframes including N retransmitted MPDUs are located at the preset position of the second A-MPDU, such as at the start position, the middle position or the end position of the second A-MPDU. Since A-MPDU may contain one or more of management frame, control frame, and data frame, if only the data frame supports HARQ transmission, then the retransmitted MPDU only needs to be placed in the preset position of all data frames, such as the start position, Middle position or end position. The preset location may be specified by the protocol or designated by the AP, or the AP and the STA may negotiate and decide. The sequence of the N A-MPDU subframes in the second A-MPDU is the same as the sequence of the N A-MPDU subframes in the first A-MPDU.

Each A-MPDU subframe included in the second A-MPDU also corresponds to a tail bit part. The tail bit part includes at least 6 bits and takes a preset value. For example, a tail bit part may be located in an A-MPDU. After the subframe, it can also be located in the last few bits of the A-MPDU subframe. In step S203, the tail bit filling method is the same as the tail bit filling method in step S201, and the tail bit filling method used in the retransmission and the previous transmission is the same.

The first A-MPDU is carried in the data field of a first PPDU. The second A-MPDU is carried in the data field of a second PPDU. The first PPDU also includes a physical layer preamble, and the second PPDU also includes a physical layer preamble.

Optionally, to support HARQ transmission, the physical layer preamble of any PPDU may also include one or more of the following:

A retransmission indication is used to indicate whether the PPDU includes a retransmitted MPDU, the retransmission indication takes a first value, and it is used to indicate that the PPDU includes a retransmitted MPDU; the retransmission indication takes a second value, It is used to indicate that the PPDU does not include the retransmitted MPDU; in other words, the retransmission indication is used to tell the receiver whether it is necessary to perform HARQ LLR combined decoding for the retransmitted MPDU in this PPDU and the MPDU received in error last time, or Joint decoding.

Modulation and coding scheme indication, if the modulation and coding scheme indication is a special value, the special value is used to indicate that the PPDU only includes retransmitted MPDUs; that is, the PPDU does not include non-retransmitted MPDUs.

The retransmission length indicator is used to indicate the total length or total duration of the N A-MPDU subframes included in the PPDU; optionally, if the retransmission indicator indicates that the PPDU does not include a retransmission MPDU, the retransmission length indicator It can be omitted or set to a reserved value. If the retransmission indication indicates that the PPDU includes a retransmission MPDU, the retransmission length indication is used to indicate the total length or total duration of the N A-MPDU subframes corresponding to the N MPDUs. In addition, the retransmission indication information can also be included in the total length or total duration field of N A-MPDU subframes, that is, the total length of N A-MPDU subframes. When the total virtual length or total duration field is equal to 0, then It indicates that the PPDU does not include a retransmitted MPDU, if other values are yes, it indicates that the PPDU includes a retransmitted MPDU, and the value is the total length of N A-MPDU subframes, or the total duration.

The tail bit part position indicator is used to indicate the position of the tail bit part corresponding to the last A-MPDU subframe in the N A-MPDU subframes. Optionally, if the MPDU retransmission indication indicates that the PPDU does not include a retransmission MPDU, the position indication of the tail bit part may be omitted, or may be set to a reserved value. If the MPDU retransmission indicator indicates that the PPDU includes a retransmitted MPDU, the tail bit position indicator is used to indicate the retransmission of the tail bit corresponding to the last A-MPDU subframe of the N A-MPDU subframes corresponding to the N MPDUs Part of the location. The tail bit position indication can also be used to indicate whether the PPDU includes a retransmitted MPDU. For details, please refer to the description in the first embodiment.

It should be noted that the above-mentioned instruction information can also be applied to other embodiments and is not limited to this embodiment. It can be understood that the first PPDU does not include a retransmission MPDU, and therefore, the retransmission indication of the first PPDU indicates that the first PPDU does not include a retransmission MPDU. The second PPDU includes a retransmission MPDU, and therefore, the retransmission indication of the second PPDU indicates that the second PPDU includes a retransmission MPDU.

After the A-MPDU subframe is encapsulated into an A-MPDU, the sender needs to perform BCC encoding on the A-MPDU. In an example, the N A-MPDU subframes in the first A-MPDU correspond to the first transmitted coded bits obtained by BCC encoding using the first transmitted coding parameter encoding; the N A-MPDU subframes in the second A-MPDU correspond to Retransmission coding parameters are used to encode the retransmission coded bits obtained by BCC coding; wherein the retransmission coding parameters are the same as the first transmission coding parameters or have a preset relationship. Optionally, the transmitting end may also perform scrambling on the encoded bits of the A-MPDU subframe, after processing such as constellation point mapping, and send it out via the antenna.

The coding parameters (retransmission coding parameters and first transmission coding parameters) include: code rate, and a generator matrix corresponding to the code rate; optional also includes puncturing mode. The retransmission coding parameters are the same as the first transmission coding parameters. It can be: the code rate, and the corresponding generator matrix of the code rate is the same, optional, if the coding parameters include puncturing mode, retransmission and first transmission puncturing The pattern is also the same. The preset relationship between the retransmission coding parameters and the first transmission coding parameters can be: the code rate, and the corresponding multinomial matrix of the code rate is the same. If the coding parameters include the puncturing mode, the retransmission and the first transmission puncturing mode exist With a preset relationship, the coded bits obtained by retransmitting the puncturing mode and the coded bits obtained by the first transmission of the puncturing mode can be combined into the bits obtained after the new puncturing mode or the coded bits without puncturing.

Optionally, performing BCC encoding on the N A-MPDU subframes includes but is not limited to the following two methods:

1) For HARQ CC, the same coding parameters (including the code rate, and the corresponding generator matrix of the code rate, as well as the optional code rate) are used for the A-MPDU subframes corresponding to a single retransmitted MPDU or at least two consecutive retransmitted MPDUs. Hole mode), perform BCC coding. The retransmission coding parameter and the first transmission coding parameter may be the same as: the code rate used for the retransmission and the previous transmission, and the code rate corresponding to the generator multinomial matrix is the same. Optionally, the puncturing mode used is the same.

2) For HARQ IR, perform BCC coding with the same parameters on the A-MPDU subframes corresponding to a single retransmitted MPDU or at least two consecutive retransmitted MPDUs, including the code rate and its corresponding generation matrix. Then the coded bits are periodically punctured according to another puncturing mode different from the previously transmitted puncturing mode to generate punctured coded bits. The puncturing mode used in retransmission is different from the puncturing mode used in the previous transmission. There is a preset relationship. The coded bits generated by the puncturing mode of the retransmission and the puncturing mode of the previous transmission can be combined as another new puncturing. Pattern or coded bits generated without puncturing. Therefore, the preset relationship between the retransmission coding parameters and the first transmission coding parameters can be: the retransmission and the previous transmission use the same code rate, the corresponding generator matrix of the code rate is the same, and the retransmission uses the same puncturing mode as the previous transmission. There is a preset relationship in the punch mode of.

The following examples illustrate. Fig. 6a, Fig. 6b, Fig. 6c and Fig. 6d take an example where a tail bit is located (or filled in) after an A-MPDU subframe as an example.

As shown in Figure 6a, the first A-MPDU transmitted first includes A-MPDU subframes 1 to 5 in turn, and also includes 5 tail bits corresponding to the 5 A-MPDU subframes, respectively It is tail bit 1 to tail bit 5, and the value of each tail bit part is a preset value, for example, the tail bit includes 6 bits and the value is 00000. The first A-MPDU is encoded using the first-pass encoding parameter to obtain BCC encoded bits.

For example, the sender determines that the consecutive MPDU2 and MPDU3 in the first A-MPDU need to be retransmitted, and MPDU2 is included in A-MPDU subframe 2, MPDU3 is included in A-MPDU subframe 3, and the sender also needs to transmit A- MPDU subframe 6 and A-MPDU subframe 7. As shown in Figure 6b, the sender sends a second A-MPDU. The second A-MPDU includes A-MPDU subframe 2, A-MPDU subframe 3, A-MPDU subframe 6 and A-MPDU subframe 7, where A-MPDU subframe 2 includes tail bit 2, A-MPDU subframe 3 is tail bit 3, A-MPDU subframe 6 is tail bit 6, and A-MPDU subframe 7 is tail bit 7, and every Each tail bit is a preset value, which is the same as the preset value of the tail bit in the first A-MPDU. Perform BCC coding on the second A-MPDU to obtain BCC coded bits. Among them, retransmission coding parameters are used for A-MPDU subframe 2 and A-MPDU subframe 3, and the retransmission coding parameters and the first transmission coding parameters can be the same or exist Default relationship.

For another example, the sender determines that non-contiguous MPDU2 and MPDU4 in the first A-MPDU subframe need to be retransmitted, and MPDU2 and MPDU4 are contained in A-MPDU subframe 2 and A-MPDU subframe 4, respectively. As shown in Figure 6c, the sender sends A-MPDU subframe 2 and A-MPDU subframe 4, and also sends A-MPDU subframe 6 and A-MPDU subframe 7, and A-MPDU subframe 2 includes Tail bit 2, A-MPDU subframe 4 includes tail bit 4, A-MPDU subframe 6 includes tail bit 6, A-MPDU subframe 7 includes tail bit 7, for A-MPDU subframe 2 and A- The MPDU subframe 3 uses the retransmission coding parameter to perform BCC coding to obtain the retransmission coding bit. The retransmission coding parameter and the first transmission coding parameter may be the same or have a preset relationship.

For another example, the sender determines that consecutive MPDU1 and MPDU2 in the first A-MPDU subframe need to be retransmitted, and a single MPDU4 needs to be retransmitted. As shown in Figure 6d, the sender sends

A-MPDU subframes

1, 2 and 4, and also sends

A-MPDU subframes

6 and 7, and A-MPDU subframe 1 includes tail bit 1, A-MPDU subframe Frame 2 includes tail bit 2, A-MPDU subframe 4 includes tail bit 4, A-MPDU subframe 6 includes tail bit 6, A-MPDU subframe 7 includes tail bit 7, for A-MPDU subframe 1. In A-MPDU subframe 2 and A-MPDU subframe 4, retransmission coding parameters are used to perform BCC coding to obtain retransmission coding bits. The retransmission coding parameters and the first transmission coding parameters may be the same or have a preset relationship.

7a, 7b, 7c, and 7d are illustrated by taking the tail bit part located in the last few bits of an A-MPDU subframe as an example. For the filling method of the last few bits, please refer to the foregoing embodiment, which will not be repeated here.

As shown in Figure 7a, the first A-MPDU includes A-MPDU subframes 1 to 5 in sequence, wherein the last few bits of each A-MPDU subframe are tail bits, and each tail bit is a preset value. For example, all 0s.

As shown in Figure 7b, the sender determines that consecutive MPDU2 and MPDU3 need to be retransmitted, and the second A-MPDU includes

A-MPDU subframes

2 and 3, and

A-MPDU subframes

6 and 7;

As shown in Figure 7c, the sender determines that non-contiguous MPDU2 and MPDU4 need to be retransmitted, and the sender sends a second A-MPDU. The second A-MPDU includes

A-MPDU subframes

2 and 4, and A-MPDU subframe 6. And 7;

As shown in Figure 7d, the sender determines that consecutive MPDU1 and MPDU2 need to be retransmitted, and a single MPDU4 needs to be retransmitted. The sender sends a second A-MPDU, and the second A-MPDU includes

A-MPDU subframes

1, 2 and 3. , And

A-MPDU subframes

6 and 7.

Since the tail bits in the first A-MPDU and the second A-MPDU are both preset values, the initial state of the BCC encoding of the previously transmitted A-MPDU subframe and the initial state of the retransmitted A-MPDU subframe are both tail The bit part and the end state are all tail bit parts, so the second A-MPDU can be encoded to obtain a block of BCC encoded bits, which reduces the coding complexity of the sender. And it enables the receiving end to combine and decode the LLR of the first transmitted coded bit and the LLR of the retransmitted coded bit, thus realizing the HARQ supporting the A-MPDU structure in the WLAN and improving the transmission reliability of the WLAN system Sex.

Embodiment 3 For the foregoing first process (that is, the sender first encodes, then scrambles, and correspondingly, the receiver first descrambles and then decodes), a detailed description of the embodiment of the present application provides a method for receiving retransmitted data , In order to improve the transmission reliability and transmission efficiency of the wireless communication system. The third embodiment corresponds to the second embodiment. Since the information bits are first encoded and then scrambled, the scrambling code sequence used for each A-MPDU transmission may be the same or different.

FIG. 8 shows a method for receiving retransmitted data according to an embodiment of the present application, including:

S301: Receive a first A-MPDU, where the first A-MPDU includes M A-MPDU subframes and M tail bit parts, and one tail bit part corresponds to one A-MPDU subframe. M is greater than or equal to 1.

Correspondingly, optionally, the receiving end performs processing such as constellation point demapping, descrambling, and decoding on the received signal, and then parses to obtain the first A-MPDU. For the detailed introduction of the first A-MPDU and the tail bit filling method, please refer to the description in the foregoing embodiment S201, which will not be repeated here.

Optionally, the receiving end can determine which MPDUs in the first A-MPDU are received correctly and which MPDUs are not received correctly. Therefore, the receiving end can feed back confirmation information to the sending end to indicate which MPDUs in the first A-MPDU are received successfully , Which received failed. The confirmation information can be a block confirmation frame, confirmation frame or other frames. After receiving the confirmation information, the receiving end can determine which MPDUs in the first A-MPDU need to be retransmitted. Please refer to step S202 in the foregoing embodiment, which will not be repeated here.

Optionally, the receiving end determines that N MPDUs in the first A-MPDU need to be retransmitted, and the N MPDUs are respectively included in the N A-MPDU subframes of the first A-MPDU; the N is greater than or equal to 1. , The M is greater than or equal to N.

S302: Receive a second A-MPDU, where the second A-MPDU includes the N A-MPDU subframes and N tail bit portions corresponding to the N A-MPDU subframes; one tail bit portion includes at least 6 bits, at least 6 bits are preset values; N A-MPDU subframes include N MPDUs, and N MPDUs are MPDUs that need to be retransmitted in the first A-MPDU. N is greater than or equal to 1, and M is greater than or equal to N.

For the detailed introduction of the second A-MPDU and the method of filling the tail bits, refer to the description in the foregoing embodiment S203, which will not be repeated here.

S303: For N A-MPDU subframes in the first A-MPDU, the LLR of the first transmission coded bit encoded by the first transmission coding parameter is used, and the N A-MPDU subframes in the second A-MPDU The LLR of the retransmission coded bits encoded by the retransmission coding parameter is combined or jointly decoded to obtain N A-MPDU subframes; wherein, the retransmission coding parameter is the same as the first transmission coding parameter or There is a preset relationship.

Optionally, in addition to the N retransmitted MPDUs, the second A-MPDU may also include other MPDUs, and the other MPDUs are newly transmitted MPDUs. Optionally, the BCC coding parameters used by the retransmitted MPDU may be different from the BCC coding parameters used by the newly transmitted MPDU, including the code rate and the puncturing mode. If for HARQ CC, the code rate used in the A-MPDU subframe containing the retransmitted MPDU, the puncturing mode is the same as the code rate and puncturing mode used in the A-MPDU subframe that transmits the MPDU previously. If for HARQ IR, the A-MPDU subframe containing the retransmitted MPDU and the A-MPDU subframe containing the previously transmitted MPDU use different bit rates and puncturing modes, but the encoded bits can be regarded as coming from a low code Rate the different parts of the BCC encoded bits.

The LLR of the retransmission coded bit corresponding to the N A-MPDU subframes in the second A-MPDU and the LLR of the first transmission coded bit of the N A-MPDU subframes previously transmitted in the first A-MPDU by the receiving end , Perform combined decoding or joint decoding. The receiving end also performs BCC decoding on the coded bits corresponding to the A-MPDU subframe of the newly transmitted MPDU in the possible second A-MPDU.

When performing BCC decoding on the BCC coded bits of the N A-MPDU subframes corresponding to the N retransmitted MPDUs, the receiver can learn that the second A-MPDU includes the A-MPDU subframes of the retransmitted MPDU in the following manner The corresponding tail bit position.

The first way: the receiving end learns the total length or total duration of N A-MPDU subframes including N retransmitted MPDUs through the retransmission length indication.

The second way: the receiving end learns the position of the tail bit corresponding to the last A-MPDU subframe containing the retransmitted MPDU in the N A-MPDU subframes through the position indication of the tail bit part.

The third method: the receiving end MAC layer searches the beginning of each A-MPDU subframe with a 4-byte MPDU delimiter through every 4-byte sliding window (the MPDU delimiter is 4 bytes and contains the MPDU length indication information. In addition, A- The MPDU subframe is also an integer multiple of 4 bytes) to obtain the total length of all A-MPDU subframes including the retransmitted MPDU; if the entire previously transmitted first A-MPDU is all wrong, the receiving end can carry the first A- The length field in the L-SIG field of the traditional preamble (Non-HT preamble) of the first PPDU of the MPDU and the fixed length of the preamble of the PPDU are used to calculate the total length of all A-MPDU subframes in the first A-MPDU to obtain the first The last one in the A-MPDU contains the tail bit position corresponding to the A-MPDU subframe of the retransmitted MPDU.

Optionally, the third method is used to obtain the position of the tail bit, the preamble of the PPDU may not include: retransmission length indication and/or tail bit position indication, and N A-MPDU subframes are in the first A-MPDU The sequence of is the same as the sequence of the N A-MPDU subframes in the second A-MPDU.

For HARQ CC, the receiving end will determine the LLR of the BCC coded bits in the A-MPDU subframes containing the retransmitted MPDU (the N A-MPDU subframes in the aforementioned second A-MPDU) and the LLR of the MPDU received in error last time. The LLRs of the BCC coded bits of the A-MPDU subframes (the N A-MPDU subframes in the aforementioned first A-MPDU) are combined and decoded.

For HARQ IR, the receiving end will determine the LLR of the BCC coded bits of the A-MPDU subframe containing the retransmitted MPDU (the aforementioned N A-MPDU subframes) and the last A-MPDU subframe containing the incorrectly received MPDU (the aforementioned The LLRs of the BCC coded bits of the N A-MPDU subframes in the first A-MPDU are jointly decoded. For example, when the first A-MPDU is transmitted previously, the BCC code of the 5/6 code rate in the existing wifi protocol (obtained by puncturing the BCC code bit with the code rate of the mother codebook 1/2), the retransmitted BCC The coded bits are also obtained by puncturing the BCC coded bits of the mother codebook with a code rate of 1/2. The BCC coded bits obtained twice can form a BCC code of another code rate, such as a BCC code of a code rate of 3/4. The BCC code of rate 3/4 may be different from the BCC code of rate 3/4 used in the current WiFi protocol, or it may be the same.

Based on whether each MPDU in the received second A-MPDU is received correctly, the receiving end can give feedback on each MPDU in the second A-MPDU, including no reply, NACK, ACK, Block ACK and Multi-STA Block Ack and other methods are not repeated here.

Since the tail bits in the first A-MPDU and the second A-MPDU are both preset values, the initial state of the BCC encoding of the previously transmitted A-MPDU subframe and the initial state of the retransmitted A-MPDU subframe are both tail The bit part and the end state are all tail bits part, so that the receiving end can combine and decode the LLR of the first transmitted coded bit and the LLR of the retransmitted coded bit, thus realizing the support of A-MPDU in WLAN Structured HARQ transmission improves the transmission reliability of the WLAN system.

Embodiment 4 For the foregoing second process (ie, the sender first scrambles, then encodes, and correspondingly, the receiver first decodes and then descrambles), a detailed description of the embodiment of the present application provides a method for sending retransmitted data , In order to improve the transmission reliability and transmission efficiency of the wireless communication system. Since the information bits are first scrambled and then coded, in one example, the retransmitted scrambling code sequence needs to be the same as the first transmitted scrambling code sequence.

Fig. 9 shows a method for receiving retransmitted data provided by an embodiment of the present application.

S401: The sending end sends a first scrambled A-MPDU, where the first scrambled A-MPDU includes M scrambled A-MPDU subframes and M tail bit parts, one tail bit part Corresponding to one of the scrambled A-MPDU subframes, the M is greater than or equal to 1;

A tail bit part may be located after a scrambled A-MPDU subframe, or may be located in the last few bits of a scrambled A-MPDU subframe. Each tail bit part is a preset value and includes at least 6 bits, for example, the tail bit part is 6 bits and all 0s. It is understandable that the value of the tail bit may also be other values, and the value of the tail bit may be agreed upon by a protocol, or may be determined through negotiation between the AP and the STA, which is not specifically limited in the embodiment of the present application.

Before sending the scrambled first A-MPDU, it includes: the sender generates the first A-MPDU. The first A-MPDU includes M A-MPDU subframes and M tail bit parts, one tail bit part and one tail bit part. Corresponding to A-MPDU subframes, M is greater than or equal to 1. The sender scrambles the first A-MPDU using the previously transmitted scrambling code sequence to obtain the first scrambled A-MPDU. The first scrambled A-MPDU includes the scrambled M A-MPDUs The subframe and M are the tail bits of the preset value. Optionally, the period of the scrambling code sequence is 127 bits. For example, the 127 bit sequence is 00001110 11110010 11001001 00000010 00100110 00101110 10110110 00001100 11010100 11100111 10110100 00101010 11111010 01010001 10111000 11111111, the scrambling process can be: change the information bits of the A-MPDU from The first to last bits are XORed with a scrambling sequence with a period of 127 bits. For example, an A-MPDU contains 200 bits. First, the first 127 bits in the A-MPDU are XORed with the 127 bit sequence, and then the The last 73 bits of the A-MPDU are XORed with the first 73 bits of the 127 bits.

Further, the transmitting end sends coded bits, where the coded bits include the first transmitted coded bits, and the first transmitted coded bits are the N scrambled A-MPDU subframes in the first A-MPDU that have been scrambled. The first transmitted coded The parameters are obtained by BCC encoding.

The tail bit filling method can include PHY filling method and MAC filling method. If the PHY filling method is adopted, a tail bit part is located after the corresponding A-MPDU subframe; if the MAC filling method is adopted, a tail bit is located in a The last few bits in the A-MPDU subframe.

It should be noted that, in order to ensure that the value of the tail bit part included in the first A-MPDU that has been scrambled is still the preset value, the following methods can be used to fill and set the tail bit part:

1) PHY filling method: add 6 or more tail bits after the end of each A-MPDU subframe, the value is a preset value, such as all 0s. It can be understood that the value of the tail bit may also be other values, which is not specifically limited in the embodiment of the present application. Further, the first A-MPDU is encapsulated into the first PPDU. An implementation manner: scramble the service field and data field contained in the first PPDU, and finally the 6 or more bits added by the sender after the end of each scrambled A-MPDU subframe are replaced with a preset value Or, another implementation: only scramble the A-MPDU subframe in the first A-MPDU, and not scramble the tail bit part after the A-MPDU subframe, so the first A that has been scrambled -The tail bit part included in the MPDU is still the preset value; yet another embodiment: instead of adding at least 6 bits of tail bit part after each A-MPDU subframe, the first A-MPDU is first scrambled to obtain After the first scrambled A-MPDU, a tail bit part of at least 6 bits is added after each scrambled A-MPDU subframe and set as a preset value.

2) MAC filling method: In the existing A-MPDU structure, as shown in Figure 2, each A-MPDU subframe contains the MPDU spacer, MPDU and padding. The padding byte is 0 to 3 bytes. The bit value of is not specified. Except that the last A-MPDU subframe does not need to be an integer multiple of 4 bytes, the other A-MPDU subframes need to be 4 bytes integers, which are mainly used by the receiver to quickly find the MPDU delimiter through the 4-byte sliding window to avoid When some MPDUs are wrong, other correctly received MPDUs can still be found. The specific MAC filling method is:

I. When the A-MPDU subframe needs to be filled with 0 bytes, the A-MPDU subframe needs to be filled with additional 4 bytes, and the last 6 bits of the additional 4 bytes can be used as the tail bit part. The tail bit part of the bit needs to be set to a preset value, such as all 0s. Other padding bits can also be set to preset values.

II. When the A-MPDU subframe needs to be filled with 1 to 3 bytes, the A-MPDU subframe does not need to be filled with extra bytes, and the last 6 bits of the filled 1 to 3 bytes are used as the tail Bits, the tail bits of at least 6 bits need to be set to a preset value, such as all 0s. Other padding bits can also be set to preset values.

After using the above two MAC filling methods, the MAC layer of the transmitting end informs the PHY layer of the position of at least 6 tail bits contained in each A-MPDU subframe in the first A-MPDU, and then the PHY layer of the transmitting end responds to the MAC layer. The first A-MPDU delivered to it is encapsulated into the first PPDU. The sender scrambles the service field and data field, and then the PHY scrambles the service field and data field. Finally, the sender adds The 6 or more bits added after the end of the scrambled A-MPDU subframe is replaced with a preset value.

It is worth noting that all existing 802.11 PPDUs include a preamble, a service field, and a data field. This application does not restrict it. In order to support HARQ transmission, the service field may or may not exist.

S402: Determine N MPDUs that need to be retransmitted in the first A-MPDU, where the N MPDUs are respectively included in the N A-MPDU subframes of the M A-MPDU subframes; the N is greater than Equal to 1, the M is greater than or equal to N.

For step S402, refer to the aforementioned step S202, which will not be repeated here.

S403: Send a second scrambled A-MPDU, the second scrambled A-MPDU includes N scrambled A-MPDU subframes and N tail bits corresponding to the N A-MPDU subframes Part; a tail bit part includes at least 6 bits, and at least 6 bits are a preset value.

After confirming that N MPDUs need to be retransmitted, the sender retransmits the N MPDUs in S403; optionally, the second A-MPDU may include other MPDUs in addition to the N retransmitted MPDUs. Other MPDUs are The newly transmitted MPDU.

In retransmission, a tail bit part may be located after a scrambled A-MPDU subframe, or may be located in the last few bits of a scrambled A-MPDU subframe. Each tail bit part is a preset value and includes at least 6 bits, for example, the tail bit part is 6 bits and is all 0s or all 1s. For the filling and setting method of the tail bit, refer to S401.

Before sending the scrambled second A-MPDU, it includes: the sender generates a second A-MPDU. The second A-MPDU includes N A-MPDU subframes and N tail bit parts, one tail bit part and one tail bit part. Corresponding to A-MPDU subframes, N is greater than or equal to 1, and N A-MPDU subframes include N retransmitted MPDUs. Further, the sending end scrambles the second A-MPDU to obtain the second A-MPDU that has been scrambled, and the second A-MPDU that has been scrambled includes N number of A-MPDU subframes that have been scrambled and N One is the tail bit part of the preset value. Further, the transmitting end sends coded bits corresponding to the second A-MPDU, the coded bits include retransmission coded bits, and the retransmission coded bits are obtained by using retransmission coding parameters for the N A-MPDU subframes that have been scrambled .

For the A-MPDU subframe containing the retransmitted MPDU, the same scrambling code sequence shall be used as the A-MPDU subframe containing the MPDU previously transmitted, that is, the same periodic scrambler sequence (depending on the scrambler seed), And during the retransmission, the first bit or the nth bit of the scrambled sequence of the N A-MPDU (including the retransmission MPDU) subframe is the same as the previous transmission of the N A-MPDU subframes. The first bit or the nth bit of the used scrambling code sequence is the same respectively.

Optionally, in the second A-MPDU, the A-MPDU subframe including the newly transmitted MPDU may be scrambled by using another new periodic scrambling code sequence different from the retransmitted scrambling code sequence, for example, a scrambler The seed is generated using the existing 802.11ac/ax method, and the scrambler is the same as that used in 802.11ac/ax, generating a periodic 127-bit sequence. Of course, the A-MPDU subframe including the newly transmitted MPDU can also be scrambled by using the same periodic scrambling code sequence as the retransmitted scrambler sequence.

Optionally, the preamble of the first PPDU and the second PPDU in the fourth embodiment may also include the retransmission indication, the modulation and coding scheme indication, the retransmission length indication, or the tail as shown in the second or first embodiment. Bit position indication etc. I won't repeat them here. Optionally, the fourth embodiment may further include: a scrambler seed indication, which is used to indicate the scrambler seed used for scrambling the retransmitted MPDU.

Since the tail bits in the first A-MPDU and the second A-MPDU are both preset values, the initial state of the BCC encoding of the previously transmitted A-MPDU subframe and the initial state of the retransmitted A-MPDU subframe are both tail The bit part and the end state are all tail bits part, so that the receiving end can combine and decode the LLR of the first transmitted coded bit and the LLR of the retransmitted coded bit, thus realizing the support of the A-MPDU structure in WLAN HARQ, and improve the transmission reliability of the WLAN system.

Embodiment 5 For the foregoing second process (that is, the sender first scrambles, then encodes, and correspondingly, the receiver first decodes and then descrambles), a detailed description of the embodiment of the present application provides a method for receiving retransmitted data , In order to improve the transmission reliability and transmission efficiency of the wireless communication system. Since the information bits are first scrambled and then coded, in one example, the retransmitted scrambling code sequence needs to be the same as the first transmitted scrambling code sequence. The fifth embodiment corresponds to the fourth embodiment.

FIG. 10 shows a method for receiving retransmitted data according to an embodiment of the present application, including:

S501: Receive the first scrambled A-MPDU, where the first scrambled A-MPDU includes M scrambled A-MPDU subframes and M tail bit parts, one tail bit part and one A-MPDU Corresponding to subframes, M is greater than or equal to 1.

Correspondingly, optionally, the receiving end performs processing such as constellation point demapping, decoding, and descrambling on the received signal, and then parses to obtain the first A-MPDU. For the detailed introduction of the first A-MPDU and the filling method of the tail bits, refer to the description in the foregoing embodiment S401, which is not repeated here.

Here, the receiving end determines that N MPDUs in the first A-MPDU need to be retransmitted, and the N MPDUs are respectively included in the N A-MPDU subframes of the first A-MPDU; the N is greater than or equal to 1, The M is greater than or equal to N.

S502: Receive a second scrambled A-MPDU, where the second scrambled A-MPDU includes N scrambled A-MPDU subframes and corresponding to the N scrambled A-MPDU subframes N tail bit parts; one tail bit part includes at least 6 bits, and at least 6 bits are preset values; N A-MPDU subframes include N MPDUs, and N MPDUs are the MPDUs that need to be retransmitted in the first A-MPDU , N is greater than or equal to 1, and M is greater than or equal to N.

For the detailed introduction of the second A-MPDU and the tail bit filling method, please refer to the description in the foregoing embodiment S403, which will not be repeated here.

S503: For the N A-MPDU subframes that have been scrambled in the first A-MPDU that have been scrambled, the LLR of the first-transmission coded bit encoded by the first-transmission coding parameter is used, and the second A-MPDU that has been scrambled Among the N scrambled A-MPDU subframes, the LLR of the retransmission coded bits encoded by the retransmission coding parameter is used for combined decoding or joint decoding to obtain the scrambled N A-MPDU subframes; , The retransmission coding parameter is the same as the first transmission coding parameter or has a preset relationship.

Further, it also includes: descrambling the scrambled N A-MPDU subframes to obtain the N A-MPDU subframes, so as to realize HARQ transmission of the N MPDUs included in the N A-MPDU subframes.

Optionally, in addition to the N retransmitted MPDUs, the second A-MPDU may of course also include other MPDUs, and the other MPDUs are newly transmitted MPDUs. Optionally, the BCC coding parameters used by the retransmitted MPDU and the BCC coding parameters used by the newly transmitted MPDU may be different, including the code rate and the puncturing mode. If for HARQ CC, the code rate used in the A-MPDU subframe that contains the retransmitted MPDU, the puncturing mode is the same as the code rate and puncturing mode used in the previous A-MPDU subframe that transmits the MPDU. If for HARQ IR, the A-MPDU subframe containing the retransmitted MPDU and the A-MPDU subframe containing the previously transmitted MPDU use different bit rates and puncturing modes, but the encoded bits can be regarded as coming from a low code Rate the different parts of the BCC encoded bits.

The LLR of the retransmission coded bit corresponding to the N A-MPDU subframes in the second A-MPDU by the receiving end, and the LLR of the first transmission coded bit of the N A-MPDU subframes previously transmitted in the first A-MPDU , Perform combined decoding or joint decoding. The receiving end also performs BCC decoding on the coded bits corresponding to the A-MPDU subframe of the newly transmitted MPDU in the second A-MPDU that may exist.

The first A-MPDU is carried in the data field of the first PPDU. The second A-MPDU is carried in the data field of the second PPDU. The first PPDU also includes a physical layer preamble, and the second PPDU also includes a physical layer preamble. Optionally, the physical layer preambles of the first PPDU and the second PPDU in the fifth embodiment may also include the retransmission indication, the modulation and coding scheme indication, the retransmission length indication, or the retransmission indication shown in the second or first embodiment, or Position indication of tail bits, etc. I won't repeat them here. Optionally, the PPDU of the fifth embodiment may further include: a scrambler seed indication, which is used to indicate the scrambler seed used for scrambling the retransmitted MPDU. In addition, in the fifth embodiment, the receiving end can also learn the position of the tail bit based on a variety of methods. You can refer to the three methods (the first method, the second method and the third method) in the foregoing embodiment two, which will not be repeated here. Repeat.

Since the initial state of the BCC encoding and the initial state of the retransmitted A-MPDU subframe are both tail bits, and the end state is both tail bits, the receiver can compare the LLR of the first transmitted coded bit and the retransmitted coded bit The combined decoding and joint decoding of the LLR of the WLAN realizes the HARQ transmission supporting the A-MPDU structure in the WLAN, and improves the transmission reliability of the WLAN system.

Embodiment 6 For the foregoing first process (ie, the transmitter first encodes, then scrambles, and correspondingly, the receiver first descrambles, then decodes), a detailed description is provided in the embodiment of this application for a method for sending retransmitted data , In order to improve the transmission reliability and transmission efficiency of the wireless communication system. Since the information bits are first encoded and then scrambled, the scrambling code sequence used for each A-MPDU transmission may be the same or different.

FIG. 11 shows a schematic flowchart of a method for receiving retransmitted data according to an embodiment of the present application, and the method includes:

S601: Send a first A-MPDU, where the first A-MPDU includes M A-MPDU subframes, and the M is greater than or equal to 1.

The first A-MPDU is included in the data field of the first PPDU, and the first PPDU also includes a physical layer preamble.

S602: Determine N MPDUs that need to be retransmitted in the first A-MPDU, where the N MPDUs are respectively included in N A-MPDU subframes of the M A-MPDU subframes; the N is greater than Equal to 1, the M is greater than or equal to N.

For step S602, refer to the aforementioned step S202, which will not be repeated here.

S603: Send a second A-MPDU, where the second A-MPDU includes the N A-MPDU subframes, and the N A-MPDU subframes include the N retransmission MPDUs;

The second A-MPDU is included in the data field of the second PPDU, and the second PPDU also includes a physical layer preamble.

The N A-MPDU subframes including N retransmitted MPDUs are located at the preset position of the second A-MPDU, such as at the start position, the middle position or the end position of the second A-MPDU. Since A-MPDU may contain one or more of management frame, control frame, and data frame, if only the data frame supports HARQ transmission, then the retransmitted MPDU only needs to be placed in the preset position of all data frames, such as the start position, Middle position or end position. The preset location may be specified by the protocol or designated by the AP, or the AP and the STA may negotiate and decide. The sequence of the N A-MPDU subframes in the second A-MPDU is the same as the sequence of the N A-MPDU subframes in the first A-MPDU.

The N retransmitted MPDUs include at least one of the first type of retransmitted MPDU and the second type of retransmitted MPDU. Among the N A-MPDU subframes, the initial state of performing BCC encoding on the A-MPDU subframe of the first retransmission MPDU or the A-MPDU subframe of the second retransmission MPDU is: the first A- In the MPDU, at least the last 6 bits of the A-MPDU subframe that is correctly received before the A-MPDU subframe of the first type of retransmission MPDU or the A-MPDU subframe of the second type of retransmission MPDU are located, and the first The end state of performing BCC encoding on an A-MPDU subframe of a retransmitted MPDU or an A-MPDU subframe of a second retransmitted MPDU is: in the first A-MPDU located in the first retransmitted MPDU At least the first 6 bits of the A-MPDU subframe after the A-MPDU subframe of the second type of retransmission MPDU and the A-MPDU subframe that has been correctly received, the first 6 bits are used as the information tail bits.

When the N retransmitted MPDUs are retransmitted, the A-MPDU subframes including the first retransmitted MPDU and the A-MPDU subframes including the second retransmitted MPDU are respectively subjected to BCC encoding. Regardless of the type of retransmitted MPDU, the initial state and end state of BCC encoding are at least 6 bits of information correctly received before and after the first or second type of retransmitted MPDU, respectively, and the information received correctly before and after the adjacent At least 6 bits are respectively included in the A-MPDU subframes that have been correctly accepted before and after the adjacent A-MPDU subframes including the retransmitted MPDU. The BCC encoding parameters used in the retransmission and the previous transmission may include the code rate, and the generation of multiple matrices, and optionally, the puncturing mode. Optionally, the retransmission coding parameter is the same as the first transmission coding parameter or there is a preset relationship.

Optionally, to support HARQ, the physical layer preamble of the first PPDU and/or the second PPDU further includes one or more of the following:

A retransmission indicator is used to indicate whether the PPDU includes a retransmitted MPDU, the retransmission indicator takes a first value, and is used to indicate that the PPDU includes a retransmitted MPDU; the retransmission indicator takes a second value for Indicate that the PPDU does not include the retransmitted MPDU; in other words, the retransmission indication is used to tell the receiver whether it is necessary to perform HARQ LLR combined decoding or joint translation for the retransmitted MPDU in this PPDU and the MPDU received in error last time. code;

Modulation and coding scheme indication, if the modulation and coding scheme indication is a special value, the special value is used to indicate that the PPDU only includes retransmitted MPDUs; that is, the PPDU does not include non-retransmitted MPDUs;

The retransmission length indicator is used to indicate the total length or total duration of N A-MPDU subframes including N retransmitted MPDUs in the PPDU; optionally, if the retransmission indicator indicates that the PPDU does not include retransmission For MPDU, the retransmission length indication can be omitted, or it can be set to a reserved value. If the retransmission indicator indicates that the PPDU includes a retransmitted MPDU, the retransmission length indicator is used to indicate the total length or total duration of the N A-MPDU subframes corresponding to the N MPDUs.

The end state position indication is used to indicate that the A-MPDU subframe of the first type of retransmission MPDU and/or the A-MPDU subframe of the second type of retransmission MPDU in the N A-MPDU subframes are BCC encoded End state, that is, when retransmitting an A-MPDU subframe that includes the first type of retransmitted MPDU or an A-MPDU subframe that includes the second type of retransmitted MPDU, at least 6 additional information bits are transmitted when using BCC encoding Position, the at least 6 information bits have been correctly received; the at least 6 information bits are after the A-MPDU subframe including the first type of retransmitted MPDU or the A-MPDU subframe including the second type of retransmitted MPDU At least the first 6 bits of the A-MPDU subframe that has been correctly received. Optionally, if the retransmission indication indicates that the PPDU does not include a retransmission MPDU, the tail end status position indication may be omitted, or may be set to a reserved value. If the retransmission indication indicates that the PPDU includes a retransmission MPDU, the end state position indication is used to indicate the position of the end state corresponding to the N A-MPDU subframes corresponding to the N MPDUs. It should be noted that the end state position indication needs to indicate the end state of each first type of retransmitted MPDU and each second type of MPDU. If the N retransmitted MPDUs only include one first retransmitted MPDU (single retransmitted MPDU) or one second retransmitted MPDU (consecutive multiple retransmitted MPDUs), the end status position indication only needs to indicate a first The position of the end state corresponding to one or the second retransmission MPDU, but if the N retransmission MPDUs include multiple retransmission MPDUs of the first type and/or multiple retransmission MPDUs of the second type, the end state position indication is required Indicate the position of the end state corresponding to each first retransmitted MPDU and/or each second retransmitted MPDU.

It should be noted that the foregoing indication information carried in the preamble of the PPDU can also be applied to other embodiments, and is not limited to this embodiment.

Optionally, in order to support HARQ, performing BCC encoding on the N A-MPDU subframes includes but is not limited to the following two methods:

1) For HARQ CC, the A-MPDU subframe corresponding to the MPDU to be retransmitted (the first retransmission MPDU) or the continuous MPDU to be retransmitted (the second retransmission MPDU) and the A-MPDU subframe after the A-MPDU subframe At least 6 bits of information that has been correctly received are subjected to the same parameters, including the bit rate, and the corresponding generator matrix, as well as the optional puncturing mode, for BCC encoding. The initial state of BCC encoding is at least 6 bits of information that has been correctly received before the A-MPDU subframe, and the end state is at least 6 bits of information that has been correctly received after the A-MPDU subframe.

It is worth noting that the BCC encoding parameters include code rate, generating multinomial matrix, and puncturing mode. Generally speaking, for the standard protocol of application products, one code rate corresponds to one generator multinomial matrix (currently considered to be the best), and optionally includes a puncture mode. In academic discussions, different generator matrices and puncturing modes can be used for each bit rate.

2) For HARQ IR, the A-MPDU subframe corresponding to the MPDU to be retransmitted (the first type of retransmitted MPDU) or the continuous MPDU to be retransmitted (the second type of retransmitted MPDU) and the subframe after the A-MPDU At least 6 bits of information that has been correctly received are subjected to BCC encoding with the same parameters, including the bit rate and the corresponding generator matrix. The initial state of the BCC encoder is at least 6 bits of information that has been correctly received before the A-MPDU subframe, and the end state is at least 6 bits of information that has been correctly received after the A-MPDU subframe.

Then the sender periodically punctures the coded bits according to another puncturing mode that is different from the open mode used in the previous transmission to generate punctured coded bits. The puncturing mode used in the retransmission is different from the puncturing mode used in the previous transmission. The coded bits generated by the two or more puncturing modes can be combined as another new puncturing mode or without puncturing operation. The generated coded bits.

Optionally, the sender can also scramble the coded bits of the N A-MPDU subframes, and send them via the antenna after baseband and radio operations such as constellation point mapping. Optionally, N A-MPDU subframes The A-MPDU subframes corresponding to other newly transmitted MPDUs can also be aggregated and sent out.

The following examples illustrate. As shown in Figure 12a, in the previous transmission, the first A-MPDU sent by the sender includes A-MPDU subframes 1 to 5 in sequence.

The sender determines that MPDU2 and MPDU3 included in

A-MPDU subframes

2 and 3 need to be retransmitted, and it also needs to newly transmit

A-MPDU subframes

6 and 7. For example, as shown in Figure 12b, the second A-MPDU sent by the sender includes

A-MPDU subframes

2, 3, 6 and 7, and the sender performs at least the first of

A-MPDU subframes

2, 3 and A-MPDU subframe 4. Perform BCC encoding with 6 bits to obtain the first part of BCC encoded bits (retransmission encoded bits). The initial state of BCC encoding is at least the last 6 bits of A-MPDU subframe 1, and the end state is at least the first 6 bits of A-MPDU subframe 4. ; Perform BCC encoding on

A-MPDU subframes

6 and 7 to obtain the second part of BCC coded bits. The initial state can be at least 6 bits with all 0 values, and the end state is the tail bit of A-MPDU subframe 7. The end state indication information may indicate that the position of the end state of the

A-MPDU subframes

2 and 3 is at least the first 6 bits of the A-MPDU subframe 4.

For another example, as shown in Figure 12c, the sender determines that MPDU2 and MPDU4 included in

A-MPDU subframes

2 and 4 need to be retransmitted, and the

new A-MPDU subframes

6 and 7 need to be transmitted, then the second A sent by the sender -MPDU includes A-MPDU subframe 2 and A-MPDU subframe 4, and

A-MPDU subframes

6 and 7. Perform BCC coding on at least the first 6 bits of A-MPDU subframe 2 and A-MPDU subframe 3 to obtain the first part of BCC coded bits. The initial state of BCC coding is at least the last 6 bits of A-MPDU subframe 1, and the end state At least the first 6 bits of A-MPDU subframe 3; perform BCC encoding on at least the first 6 bits of A-MPDU subframe 4 and A-MPDU subframe 5 to obtain the second part of BCC encoded bits. The initial state of BCC encoding is At least the last 6 bits of A-MPDU subframe 3, the end state is at least the first 6 bits of A-MPDU subframe 5, and the second part of BCC coded bits is obtained by encoding; for A-MPDU subframe 6 and A-MPDU subframe 7 Performing BCC coding to obtain the third part of BCC coded bits, the initial state may be at least 6 bits with a value of all 0s, and the end state is the tail bit of the A-MPDU subframe 7. The end state indication information may indicate that the position of the end state of A-MPDU subframe 2 is at least the first 6 bits of A-MPDU subframe 3, and the position of the end state of A-MPDU subframe 4 is at least that of A-MPDU subframe 5. The first 6 bits.

For another example, as shown in Figure 12d, the sender determines that MPDU1, MPDU2 and MPDU4 included in

A-MDPU subframes

1, 2 and 4 need to be retransmitted, and a new transmission of

A-MPDU subframes

6 and 7 is required, then the sender sends The second A-MPDU includes

A-MPDU subframes

1, 2 and 4 and

A-MPDU subframes

6 and 7. Among them, perform BCC coding on at least the first 6 bits of

A-MPDU subframes

1, 2 and A-MPDU subframe 3 to obtain the first part of BCC coded bits, and its initial state is a preset value, which is the same as the previous transmission For example, they are all 0s, and the end state is at least the first 6 bits of A-MPDU subframe 3. Perform BCC encoding on at least the first 6 bits of A-MPDU subframe 4 and A-MPDU subframe 5 to obtain the second Part of the BCC coded bits, the initial state is at least the last 6 bits of A-MPDU subframe 3, and the end state is at least the first 6 bits of A-MPDU subframe 5, and the second part of BCC coded bits is obtained by encoding; for the A-MPDU subframe Frame 6 and A-MPDU subframe 7 are subjected to BCC encoding to obtain the third part of BCC coded bits. The initial state may be at least 6 bits with all 0 values, and the end state is the tail bit of A-MPDU subframe 7. The end state indication information may indicate that the position of the end state of

A-MPDU subframes

1 and 2 is at least the first 6 bits of A-MPDU subframe 3, and the position of the end state of A-MPDU subframe 4 is A-MPDU subframe 5. At least the first 6 bits.

Since the initial state of the retransmitted A-MPDU subframe is the information bits of the adjacent A-MPDU subframe that has been correctly received, it is the same as the initial state of the previous transmission of the A-MPDU subframe, so that the receiving end can match the first The LLR that transmits the coded bits and the LLR that retransmits the coded bits are combined and decoded, thereby realizing the HARQ supporting the A-MPDU structure in the WLAN and improving the transmission reliability of the WLAN system.

The seventh embodiment describes in detail a method for receiving retransmitted data provided by the embodiment of the present application for the foregoing first process (that is, the transmitter first encodes, then scrambles, and correspondingly, the receiver first descrambles and then decodes). In order to improve the transmission reliability and transmission efficiency of the wireless communication system. The seventh embodiment corresponds to the sixth embodiment and is applied to the receiving end. Since the information bits are first encoded and then scrambled, each A-MPDU transmission can be scrambled with a different scrambling code sequence.

As shown in Figure 13, including:

S701: Receive a first A-MPDU, where the first A-MPDU includes M A-MPDU subframes, and the M is greater than or equal to 1.

The receiving end determines the N MPDUs that need to be retransmitted in the first A-MPDU, and sends feedback information to the sender. The N MPDUs are respectively contained in the N A-MPDU subframes of the M A-MPDU subframes Medium; N is greater than or equal to 1, and M is greater than or equal to N. For the specific manner of sending feedback information, refer to the description in step S202.

S702: Receive a second A-MPDU, where the second A-MPDU includes the N A-MPDU subframes;

The N retransmitted MPDUs include at least one of the first retransmitted MPDU and the second retransmitted MPDU. Wherein, in the N A-MPDU subframes, the first type of A-MPDU subframes for retransmission of MPDUs or the second type of A-MPDU subframes for retransmission of MPDUs performs BCC encoding in the initial state of the first A-MPDU subframes. -At least the last 6 bits of the A-MPDU subframe that has been correctly received before the A-MPDU subframe of the first type of retransmitted MPDU or the A-MPDU subframe of the second type of retransmitted MPDU in the MPDU, the N A -The end state of BCC encoding in the A-MPDU subframe of the first retransmission MPDU or the A-MPDU subframe of the second retransmission MPDU in the MPDU subframe is that the first A-MPDU is in the first type At least the first 6 bits of the A-MPDU subframe after the A-MPDU subframe of the retransmitted MPDU or the A-MPDU subframe of the second type of retransmitted MPDU that has been correctly received.

S703: Use the LLR of the first-transmission coded bit obtained by encoding the first-transmission coding parameter for the N A-MPDU subframes in the first A-MPDU, and use the retransmission coding for the N A-MPDU sub-frames in the second A-MPDU The LLRs of the retransmitted coded bits obtained by parameter coding are combined or jointly decoded to obtain the N A-MPDU subframes.

The receiving end can obtain the initial state and the end state of BCC encoding of N A-MPDU subframes in a variety of ways, including but not limited to:

The first method: the receiving end learns the initial state and end state of the corresponding BCC code through the length of the A-MPDU subframe of the retransmitted MPDU and the total length of the multiple APDU subframes of the continuously retransmitted MPDU, where the initial state of the BCC code And the end state is that the adjacent A-MPDU subframe of the retransmitted MPDU or the multiple APDU subframes of the continuous retransmitted MPDU has been correctly received at least 6 bits of information and the adjacent rear has been correctly received At least 6 bits of information;

The second way: the receiving end learns the end state of BCC encoding of the A-MPDU subframe containing the retransmitted MPDU through the end state position indication;

The third method: the receiving end MAC layer searches the beginning of each A-MPDU subframe with a 4-byte MPDU delimiter through every 4-byte sliding window (the MPDU delimiter is 4 bytes and contains the MPDU length indication information. In addition, A- The MPDU subframe is also an integer multiple of 4 bytes) Get the length of the A-MPDU subframe containing the retransmitted MPDU (optionally included) and the total length of multiple APDU subframes of the continuously retransmitted MPDU (optionally included) ; If the entire A-MPDU is all wrong, the receiving end can calculate the total length of all A-MPDU subframes by using the length field in the L-SIG field of the traditional preamble (Non-HT preamble) and the fixed length of the preamble of the PPDU; When this A-MPDU is retransmitted, the initial state and the end state of the adopted BCC code are all 0s. The MAC layer feeds back the initial state and end state information to the physical layer for BCC decoding.

Similarly, if the third method is adopted, the receiving end may not use the retransmission indicator and/or the retransmission length indicator to obtain the end status. Therefore, the physical layer preamble of the PPDU may not include the retransmission indicator and/or retransmission length indicator. But at this time, the sequence of the N A-MPDU subframes in the first A-MPDU needs to be the same as the sequence of the N A-MPDU subframes in the second A-MPDU.

According to the initial state and the end state, the receiving end decodes the A-MPDU subframe corresponding to the MPDU to be retransmitted or the continuous MPDU to be retransmitted, and at least the first 6 bits of information of the A-MPDU subframe that has been correctly received later, The receiving end deletes at least the first 6 bits of information to obtain the MPDU to be retransmitted or the A-MPDU subframe corresponding to the continuous MPDU to be retransmitted. For example, as shown in Figure 12d, the receiving end decodes the first part of the BCC coded bits to obtain at least the first 6 bits in

A-MPDU subframes

1 and 2 and A-MPDU subframe 3, and deletes the A-MPDU subframe 3. At least the first 6 bits of

A-MPDU subframes

1 and 2 are obtained; the receiving end decodes the second part of the BCC coded bits to obtain at least the first 6 bits of A-MPDU subframe 4 and A-MPDU subframe 5. At least the first 6 bits, A-MPDU subframe 4 is obtained.

Optionally, the decoding method supporting HARQ includes:

For HARQ CC, the receiving end combines and decodes the LLR of the BCC coded bit of the A-MPDU subframe containing the retransmitted MPDU and the LLR of the BCC coded bit of the A-MPDU subframe containing the MPDU received in error last time.

For HARQ IR, the receiver will jointly decode the LLR of the BCC coded bit of the A-MPDU subframe containing the retransmitted MPDU and the LLR of the BCC coded bit of the A-MPDU subframe containing the MPDU received in error last time. For example, the BCC code of the 5/6 code rate in the existing wifi protocol used for the first transmission (obtained by puncturing the BCC coded bits of the mother codebook code rate 1/2), and the BCC of the second retransmission The coded bits are also obtained by puncturing the BCC coded bits of the mother codebook with a code rate of 1/2. The BCC coded bits obtained twice can form a BCC code of another code rate, such as a BCC code of a code rate of 3/4. The BCC code with rate 3/4 may be different from the BCC code with rate 3/4 used in the current WiFi protocol.

Based on whether each MPDU in the received second A-MPDU is received correctly, the receiving end can give feedback on each MPDU in the second A-MPDU, including no reply, NACK, ACK, Block ACK and Multi-STA Block Ack and other methods.

Since the initial state of the retransmitted A-MPDU subframe is the information bits of the adjacent A-MPDU subframe, which is the same as the initial state of the previous transmission of the A-MPDU subframe, the receiving end can compare the LLR of the first transmitted coded bit. Combine decoding and joint decoding with the LLR of the retransmitted coded bits, thereby realizing the HARQ supporting the A-MPDU structure in the WLAN and improving the transmission reliability of the WLAN system.

The eighth embodiment corresponds to the second process. The eighth embodiment is different from the seventh embodiment in that the sender first scrambles and then encodes the first A-MPDU, and also first scrambles and then encodes the second A-MPDU. Therefore, in the previous transmission, the scrambled N A-MPDU subframes are BCC encoded, and during retransmission, the scrambled N A-MPDU subframes are also BCC encoded. Correspondingly, the receiving end decodes first and then descrambles. Since the information bits are first scrambled and then coded, in one example, the retransmission scrambling code sequence needs to be the same as the first transmission scrambling code sequence.

Figure 14 shows yet another method for sending retransmitted data, including:

S801: Send the scrambled first A-MPDU, where the scrambled first A-MPDU includes M scrambled A-MPDU subframes, and M is greater than or equal to 1.

Before sending the scrambled first A-MPDU, it includes: generating the first A-MPDU, using the first-transmission scrambling code sequence to scramble the first A-MPDU to obtain the scrambled first A-MPDU; further Yes, use the first-pass encoding parameter to perform BCC encoding on the first A-MPDU to obtain the encoded bits, including: using the first-pass encoding parameter to perform BCC encoding on the N A-MPDU subframes in the first A-MPDU The coded bits are transmitted first.

The first A-MPDU is carried in the data field of the first PPDU, and the first PPDU also includes a physical layer preamble.

S802: Determine the N MPDUs that need to be retransmitted in the first A-MPDU, and the N MPDUs are respectively included in the N A-MPDU subframes of the M A-MPDU subframes; N is greater than or equal to 1, and the M is greater than or equal to N.

For S802, refer to the aforementioned step S202, which will not be repeated here.

S803: Send a second A-MPDU, where the second A-MPDU includes N A-MPDU subframes;

The N retransmitted MPDUs include at least one of the first retransmitted MPDU and the second retransmitted MPDU. Among the N A-MPDU subframes, the A-MPDU subframe of the first type of retransmission MPDU or the A-MPDU subframe of the second type of retransmission MPDU in the initial state of BCC encoding is that the first A-MPDU is located in The A-MPDU subframe of the first type of retransmission MPDU or the A-MPDU subframe of the second type of retransmission MPDU has been scrambled for at least the last 6 bits of the A-MPDU subframe that has been correctly received before, and the N A- The end state of the BCC encoding of the A-MPDU subframe of the first type of retransmission MPDU or the A-MPDU subframe of the second type of retransmission MPDU in the MPDU subframe is that the first A-MPDU is located in the first type of retransmission. At least the first 6 bits of the scrambled A-MPDU subframe after the A-MPDU subframe in which the MPDU is transmitted or the A-MPDU subframe in the second type of retransmitted MPDU is received correctly.

Before sending the second scrambled A-MPDU, it includes: generating a second A-MPDU, using a scrambling code sequence to scramble the second A-MPDU to obtain the second scrambled A-MPDU; further, Then perform BCC encoding on the second A-MPDU to obtain coded bits, including: retransmission coded bits obtained by performing BCC coding on N A-MPDU subframes in the second A-MPDU using retransmission coding parameters. In addition to N retransmitted MPDUs, the second A-MPDU may optionally include other non-retransmitted MPDUs. Therefore, the coded bits may also include new transmission coding parameters for other non-retransmitted A-MPDU subframes. Coded bits obtained by BCC coding. The N A-MPDU subframes including N retransmitted MPDUs are located at the preset position of the second A-MPDU, such as at the start position, the middle position or the end position of the second A-MPDU. Since A-MPDU may contain one or more of management frame, control frame, and data frame, if only the data frame supports HARQ transmission, then the retransmitted MPDU only needs to be placed in the preset position of all data frames, such as the start position, Middle position or end position. The preset location may be specified by the protocol or designated by the AP, or the AP and the STA may negotiate and decide. Optionally, the sequence of the N A-MPDU subframes in the second A-MPDU is the same as the sequence of the N A-MPDU subframes in the first A-MPDU.

The N retransmitted MPDUs include at least one of the first retransmitted MPDU and the second retransmitted MPDU. When the N retransmitted MPDUs are retransmitted, the A-MPDU subframes including the first retransmitted MPDU and the A-MPDU subframes including the second retransmitted MPDU are respectively subjected to BCC encoding. Regardless of the type of retransmitted MPDU, the initial state and the end state of the BCC encoding after scrambling are the first or second retransmitted MPDUs that are correctly received before and after the scrambled at least 6 bits of information. At least 6 bits that are correctly received adjacent to each other are included in the A-MPDU subframes that have been correctly received before and after the adjacent A-MPDU subframes including the retransmitted MPDU. The BCC encoding parameters used in the retransmission and the previous transmission may include the code rate, and the generation of multiple matrices, and optionally, the puncturing mode. Optionally, the retransmission coding parameter is the same as the first transmission coding parameter or there is a preset relationship.

In the embodiment of the present application, the physical layer preamble of the first PPDU including the first A-MPDU and the second PPDU including the second A-MPDU may also include one or more of the indication information in the sixth embodiment, here No longer. Optionally, the PPDU of the embodiment of the present application may further include: a scrambler seed indication, which is used to indicate the scrambler seed used for scrambling the retransmitted MPDU.

Since the sender first scrambles the information bits included in the A-MPDU and then encodes it, in order to enable the receiver to perform combined decoding and joint decoding, optionally, the scrambling code sequence is transmitted first and the scrambling code sequence is retransmitted the same.

Since the initial state of the retransmission of the scrambled A-MPDU subframe is the scrambled information bits of the adjacent A-MPDU subframe that has been correctly received, it is the same as the previous transmission of the scrambled A-MPDU subframe The initial state is the same, so that the receiving end can combine and decode the LLR of the first transmitted coded bit and the LLR of the retransmitted coded bit, thus realizing the HARQ supporting the A-MPDU structure in the WLAN, and improving Transmission reliability of WLAN system.

Embodiment 9 For the foregoing second process (that is, the sender first scrambles, then encodes, and correspondingly, the receiver first decodes and then descrambles), the embodiment of the present application is described in detail. FIG. 15 provides a method for retransmitting data. A receiving method to improve the transmission reliability and transmission efficiency of the wireless communication system. Since the information bits are first scrambled and then coded, in one example, the retransmitted scrambling code sequence needs to be the same as the first transmitted scrambling code sequence. The ninth embodiment corresponds to the eighth embodiment. The method includes:

S901: Receive a first scrambled A-MPDU, where the first scrambled A-MPDU includes M A-MPDU subframes that have been scrambled, and M is greater than or equal to 1.

The receiving end determines the N MPDUs that need to be retransmitted in the first A-MPDU, and the N MPDUs are respectively included in the N A-MPDU subframes of the M A-MPDU subframes; N is greater than or equal to 1, and the M is greater than or equal to N. Refer to the aforementioned step S202, which will not be repeated here.

S902: Receive a second A-MPDU, where the second A-MPDU includes N A-MPDU subframes;

Among the N A-MPDU subframes, the first A-MPDU subframe of the retransmitted MPDU or the A-MPDU subframe of the second retransmitted MPDU in the initial state of BCC encoding is: in the first A-MPDU The scrambled at least the last 6 bits of the A-MPDU subframe that is correctly received before the A-MPDU subframe of the first retransmission MPDU or the A-MPDU subframe of the second retransmission MPDU has been scrambled. -The end state of BCC encoding in the A-MPDU subframe of the first type of retransmitted MPDU or the A-MPDU subframe of the second type of retransmitted MPDU in the MPDU subframe is: the first A-MPDU is located in the first At least the first 6 bits of the scrambled A-MPDU subframe after the A-MPDU subframe of one retransmission MPDU or the A-MPDU subframe of the second retransmission MPDU and that have been received correctly.

S903: For N A-MPDU subframes in the first A-MPDU, the LLR of the first-transmission coded bit obtained by encoding by the first-transmission coding parameter is adopted, and the N A-MPDU subframes in the second A-MPDU are retransmitted and encoded The LLRs of the retransmitted coded bits obtained by parameter encoding are combined or jointly decoded to obtain the scrambled N A-MPDU subframes.

The receiving end can obtain the end state of the BCC encoding performed on the N A-MPDU subframes in a variety of ways. You can refer to the several ways in the foregoing step S703, which will not be repeated here.

The receiving end performs combined decoding or joint decoding on the LLR containing the coded bits of the A-MPDU subframe of the retransmitted MPDU and the LLR containing the coded bits of the A-MPDU subframe of the last transmission of the MPDU; optional, Use the method specified in the existing 802.11 protocol to decode the coded bits of the A-MPDU subframe containing the newly transmitted MPDU.

According to the initial state and the end state, the receiving end decodes the scrambled N A-MPDU subframes, and the subsequent scrambled at least 6 bits of information that has been correctly received. In an example, the receiving end deletes the scrambled at least 6 bits of information to obtain N A-MPDU subframes that have been scrambled, and obtain the N A-MPDU subframes after descrambling, thereby obtaining N repetitions. The transmitted MPDU. In another example, the receiving end first descrambles the scrambled N A-MPDU subframes and the scrambled at least 6 bits, and then deletes the at least 6 bits of information to obtain the N A-MPDU subframes , Thereby obtaining N retransmitted MPDUs.

When descrambling an A-MPDU subframe including a retransmitted MPDU, use the same scrambling code sequence as the A-MPDU subframe containing the MPDU last transmission to descramble the information bits obtained after combined decoding or joint decoding. Thus, N A-MPDU subframes are obtained. When descrambling the A-MPDU subframes containing the newly transmitted MPDUs, use the same method as the existing 802.11 protocol to descramble the decoded A-MPDU subframes containing the newly transmitted MPDUs, for example, through the service field The scrambler seed, which corresponds to the periodic scrambling sequence, is then descrambled.

Since the initial state of the retransmission A-MPDU subframe is the scrambled information bits of the adjacent A-MPDU subframe, it is the same as the initial state of the previous transmission of the A-MPDU subframe, and the retransmission scrambling code sequence is the same as the previous one. The transmission scrambling code sequence is the same, so that the receiving end can combine and decode the LLR of the first transmitted coded bit and the LLR of the retransmitted coded bit, thus realizing the HARQ supporting the A-MPDU structure in WLAN and improving Improve the transmission reliability of the WLAN system.

The tenth embodiment provides a method for indicating retransmission of signaling. The method includes: sending a physical layer protocol data unit PPDU, the PPDU includes a physical layer preamble and a data field, the data field includes an A-MPDU, the A-MPDU includes at least one retransmitted MPDU, and/or, at least one non- For the retransmitted MPDU, the physical layer preamble includes various retransmission indication information. Correspondingly, the receiving end receives the PPDU and parses the PPDU based on various retransmission indication information.

Optionally, the preamble of the PPDU includes:

The retransmission indication is used to indicate whether the PPDU includes a retransmitted MPDU. Here, there may be one or more retransmitted MPDUs. For example, the MPDU retransmission indication takes a first value to indicate that the PPDU includes a retransmitted MPDU, and the MPDU retransmission indication takes a second value to indicate that the PPDU does not include a retransmitted PPDU. The MPDU that needs to be retransmitted can be an unsuccessfully received MPDU in the previous transmission for HARQ transmission. The receiver will perform LLR combined decoding or joint decoding on the retransmitted MPDU and the last corresponding failed MPDU. The transmitted MPDU (or called the initial transmission MPDU) can be the MPDU successfully received in the previous transmission, and also includes the retransmitted MPDU used for ARQ transmission. Although the MPDU is retransmitted, the receiver does not need to retransmit MPDU carries on corresponding HARQ reception processing. Optionally, the receiving end that receives the retransmission indication may determine whether it is necessary to perform HARQ LLR combined decoding or joint decoding for the retransmitted MPDU in this PPDU and the corresponding MPDU received in error.

Optionally, the preamble of the PPDU includes a modulation and coding scheme indication. If the modulation and coding scheme indication is a special value, the special value is used to indicate that the PPDU includes only retransmitted MPDUs, where the retransmitted MPDUs may be It can be one or multiple. If the MPDU contained in the A-MPDU is a retransmitted MPDU, it can be indicated by using a special data modulation and coding scheme in the physical layer preamble. The special modulation and coding scheme indication takes a special value, such as an unused value Or an undefined value. Currently, the modulation and coding scheme in 802.11ax is represented by 4 bits. Currently, modulation and coding schemes 0-11 have been used, and modulation and coding schemes 12-15 are unused. Therefore, the special value can be 12-15.

Optionally, the preamble of the PPDU includes: a retransmission length indicator for indicating the total length of the A-MPDU subframe of the retransmitted MPDU included in the PPDU; the total length is in byte units, or the retransmission The length indication includes the total duration of the A-MPDU subframe of the retransmission of the MPDU. It should be noted that the total length may be a virtual total length, and may be a length calculated according to the transmission duration and the minimum transmission rate.

Optionally, the preamble of the PPDU includes: a tail bit position indicator, which is used to indicate the position of the tail bit part corresponding to the last A-MPDU subframe in the A-MPDU corresponding to the retransmitted MPDU. Optionally, if the retransmission indication indicates that the PPDU does not include a retransmission MPDU, the position indication of the tail bit part may be omitted, or may be set to a reserved value. If the retransmission indication indicates that the PPDU includes a retransmission MPDU, the tail bit part position indication is used to indicate the position of the tail bit part corresponding to the last A-MPDU subframe in the A-MPDU subframe corresponding to the retransmitted MPDU. The retransmission length indicator and/or the retransmission tail bit indicator can facilitate the receiving end to obtain the position of the tail bit, which is convenient for the receiving end to decode.

Optionally, the preamble of the PPDU includes: an end state position indication for indicating the A-MPDU subframe and/or the second type of retransmission of the MPDU of the first type among the N A-MPDU subframes The end state of the BCC encoding of the A-MPDU subframe of the MPDU, that is, when the A-MPDU subframe including the first retransmitted MPDU or the A-MPDU subframe including the second retransmitted MPDU is retransmitted, the BCC is used The position of at least 6 additional information bits transmitted during encoding, the at least 6 information bits have been correctly received; the at least 6 information bits are the A-MPDU subframes including the first type of retransmitted MPDU or the second At least the first 6 bits of the correctly received A-MPDU subframe after the A-MPDU subframe of the retransmission of the MPDU. Optionally, if the retransmission indication indicates that the PPDU does not include a retransmission MPDU, the tail end status position indication may be omitted, or may be set to a reserved value. If the retransmission indication indicates that the PPDU includes a retransmission MPDU, the end state position indication is used to indicate the position of the end state corresponding to the N A-MPDU subframes corresponding to the N MPDUs. It should be noted that the end state position indication needs to indicate the end state of each first type of retransmitted MPDU and each second type of MPDU.

The A-MPDU subframe corresponding to the retransmitted MPDU needs to be placed in the preset position of the A-MPDU included in the PPDU, such as the start position, the middle position, or the end position. Since A-MPDU may contain one or more of management frame, control frame, and data frame, if only the data frame supports HARQ transmission, then the retransmitted MPDU only needs to be placed in the preset position of all data frames or all other A- Before the MPDU subframe, such as the start position, the middle position or the end position. The preset location may be specified by the protocol or designated by the AP, or the AP and the STA may negotiate and decide. In another implementation manner, the A-MPDU subframe corresponding to the retransmitted MPDU is placed after the existing PPDU preamble and before the service field. Note: The fields included before and after the existing PPDU are the physical layer preamble, service field and A-MPDU in sequence, and optional physical layer padding bits and packet expansion.

It should be noted that the solution of the tenth embodiment can be used as a separate embodiment, can also be applied to the solutions of the aforementioned embodiment 1 to the ninth embodiment, and can also be combined with other embodiments.

Embodiment 11 provides a method for constructing a second A-MPDU. The second A-MPDU includes the A-MPDU subframe corresponding to the retransmitted MPDU and the A-MPDU subframe corresponding to the non-retransmitted MPDU. .

1. The BCC encoding parameters used for BCC encoding of A-MPDU subframes including retransmitted MPDUs may be different from the encoding parameters used for BCC encoding of A-MPDU subframes including newly transmitted MPDUs. The encoding parameters include code rate, and Generator polynomial (or generator polynomial matrix), optionally, also includes punching mode.

As the BCC in the actual product, only one type of generator polynomial is specified, such as the generator polynomial of the 802.11 series with a specified code rate of 1/2. Other code rates are realized by punching on this basis. However, in academic theory, different code rates may correspond to different generator polynomials, so the generator polynomial is also needed at this time.

2. For HARQ CC, the code rate and puncturing mode used by the A-MPDU subframe containing the retransmitted MPDU is the same as the code rate and puncturing mode used by the A-MPDU subframe containing the MPDU previously transmitted. If for HARQ IR, the A-MPDU subframe containing the retransmitted MPDU and the A-MPDU subframe containing the initial transmission of the MPDU use different code rates and puncturing modes, but the encoded bits can be regarded as coming from a low code Rate the different parts of the BCC encoded bits.

16 is a schematic structural diagram of a sending device provided by an embodiment of the present application. The sending device can be used in the sending end or the chip in the sending end. The sending device 1600 includes a processing module 1601, a sending module 1602, and a receiving module 1603. .

In an implementation manner, the sending device can be used to perform any function of the sending end in any of the foregoing Embodiment 1, Embodiment 2, Embodiment 4, Embodiment 6, and Embodiment 8, for example:

The processing module 1601 is configured to determine that the N MPDUs included in the N A-MPDU subframes in the first A-MPDU need to be retransmitted, for example, to perform the aforementioned S202, or, S402, or S602, or S802; processing module 1601 is also used to encode the first A-MPDU, or the processing module 1601 is also used to encode the second A-MPDU.

The sending module 1602 is used to send the first A-MPDU or the second A-MPDU, for example, to indicate S101, S103, S201, S203, S401, S403, S601, S603, S801, or S803.

The receiving module 1603 is configured to receive confirmation feedback information, and the confirmation feedback information is used to indicate which MPDUs in the A-MPDU have not been successfully received, for example, used to perform S102.

Optionally, it also includes a storage module 1604 for storing instructions.

In another embodiment, the sending device can be used to perform any function of the sending end in the tenth embodiment.

Processing module 1601: used to generate a physical layer protocol data unit PPDU, the PPDU includes a physical layer preamble and a data field, the data field includes an A-MPDU, the A-MPDU includes at least one retransmitted MPDU, and, at least one non- For the retransmitted MPDU, the physical layer preamble includes indication information that supports HARQ transmission.

Sending module 1602: used to send the physical layer protocol data unit PPDU.

In this embodiment of the present application, the data transmission device shown in FIG. 16 is taken as an example to describe each module in the data transmission device used at the sending end. It should be understood that the sending device used for the sending end in the embodiment of the present application can implement any one of the methods for sending retransmitted data shown in Embodiment 1, Embodiment 2, Embodiment 4, Embodiment 6, Embodiment 8 or Embodiment 10. Any function of the sender.

FIG. 17 is a schematic structural diagram of a receiving device provided by an embodiment of the present application. The receiving device 1700 can be used at the receiving end or a chip in the receiving end. The receiving device 1700 includes a processing module 1701, a sending module 1702, and a receiving module 1703.

In an implementation, the receiving device can be used to perform any function of the receiving end in any one of the foregoing

embodiments

1, 3, 5, 7 and 9, for example:

The processing module 1701 is used to determine that the N MPDUs included in the N A-MPDU subframes in the first A-MPDU need to be retransmitted; the processing module 1701 is also used to retransmit the LLR of the retransmitted coded bits and the LLR of the first transmitted coded bit Perform combined decoding or joint decoding to obtain the N A-MPDU subframes. For example, it is used to execute the aforementioned S104, S303, S503, S703, or S903.

The sending module 1702 is configured to send a confirmation feedback frame, for example, to perform the aforementioned S102, where the confirmation feedback is used to indicate which MPDUs in the A-MPDU were not successfully received.

The receiving module 1703 is used for receiving the first A-MPDU and the second A-MPDU, for example, for receiving the information sent by S102 and S103, or for performing S301 or S302, or for performing S501 or S502, or using To perform S701 or S702, or to perform S901 or S902.

Optionally, it also includes a storage module 1704, which is used to store the LLR corresponding to the first-transfer coded bit, and optionally, it is also used to store instructions.

In another embodiment, the sending device can be used to perform any function of the receiving end in the tenth embodiment.

Processing module 1701: used to parse a physical layer protocol data unit PPDU, the PPDU includes a physical layer preamble and a data field, the data field includes an A-MPDU, the A-MPDU includes at least one retransmitted MPDU, and, at least one non- For the retransmitted MPDU, the physical layer preamble includes retransmission indication information supporting HARQ.

Receiving module 1703: used to receive the physical layer protocol data unit PPDU.

For the retransmission indication information supporting HARQ, reference may be made to the specific description of the tenth embodiment or the first embodiment, which will not be repeated this time.

In the embodiment of the present application, the data transmission device shown in FIG. 17 is taken as an example to describe each module in the data transmission device used at the receiving end. It should be understood that the receiving device used for the receiving end in the embodiments of the present application has any function of the receiving end in any one of the first, third, fifth, seventh, ninth, and tenth embodiments.

The sending device (used at the sending end) or the receiving device (used at the receiving end) provided in the embodiments of this application can be implemented in a variety of product forms. For example, the sending device or the receiving device can be configured as a general processing system; for example, the sending device Or the receiving device can be implemented by a general bus architecture; for example, the sending device or the receiving device can be implemented by an application specific integrated circuit (ASIC) and so on. The following provides several possible product forms of the sending device or the receiving device in the embodiment of the present application. It should be understood that the following are only examples, which do not limit the possible product forms of the embodiment of the present application.

In an example, FIG. 18 shows a schematic block diagram of a sending device 1800 according to an embodiment of the present application. The apparatus 1800 in this embodiment of the present application may be the transmitting end in any of the foregoing method embodiments, or may be one or more chips in the transmitting end. The apparatus 1800 may be used to perform part or all of the functions of the sending end in the foregoing method embodiment.

The apparatus 1800 may be used to perform part or all of the functions of the sending end in the foregoing method embodiment. The device 1800 may include a processor 1810, a baseband circuit 1830, a radio frequency circuit 1840, and an antenna 1850. Optionally, the device 1800 may further include a memory 1820. The components of the device 1800 are coupled together via a bus 1860, where the bus system 1860 includes a power bus, a control bus, and a status signal bus in addition to a data bus. However, for clear description, various buses are marked as the bus system 1860 in the figure.

The processor 1810 may be used to control the sending end, to execute the processing performed by the sending end in the above-mentioned embodiment, and to execute the processing procedures related to the sending end in the above-mentioned method embodiments and/or other technologies used in the technology described in this application. During the process, the operating system can also be run, which is responsible for managing the bus and can execute programs or instructions stored in the memory.

The baseband circuit 1830, the radio frequency circuit 1840, and the antenna 1850 can be used to support the sending and receiving of information between the sending end and the receiving end involved in the foregoing embodiment, so as to support wireless communication between the sending end and the receiving end.

In an example, at the sending end, the retransmission or initial transmission of MPDU is processed by the processor 1810, and after the baseband circuit 1830 is encapsulated into A-MPDU according to the protocol, it is then subjected to baseband processing such as scrambling and encoding, and further processed by the radio frequency circuit After 1840 performs radio frequency processing such as analog conversion, filtering, amplification and up-conversion, it is transmitted through the antenna 1850. In another example, the confirmation feedback information sent from the receiving end is received via the antenna 1850, filtered, amplified, down-converted, and digitized by the radio frequency circuit 1840, and then decoded by the baseband circuit 1830, and decapsulated data according to the protocol. After that, the processor 1810 performs processing to restore the definite feedback information sent by the receiving end;

The memory 1820 may be used to store the program code and data of the sending end, and the memory 1820 may be the storage module 1830 in FIG. 18. It is understandable that the baseband circuit 1830, the radio frequency circuit 1840, and the antenna 1850 can also be used to support the transmitter to communicate with other network entities, for example, to support the transmitter to communicate with the network element on the core network side. The memory 1820 in FIG. 18 is shown as being separated from the processor 1810. However, those skilled in the art can easily understand that the memory 1820 or any part thereof may be located outside the channel resource allocation device 1800. For example, the memory 1820 may include a transmission line and/or a computer product separated from the wireless node, and these media can be accessed by the processor 1810 through the bus interface 1860. Alternatively, the memory 1820 or any part thereof may be integrated into the processor 1810, for example, it may be a cache and/or a general-purpose register.

It is understandable that Fig. 18 only shows a simplified design of the sending end. For example, in practical applications, the sending end may include any number of transmitters, receivers, processors, memories, etc., and all sending ends that can implement the present invention are within the protection scope of the present invention.

The embodiments of the present application describe in detail the schematic structure of the receiving device. In an example, FIG. 19 shows a schematic block diagram of a receiving apparatus 1900 according to an embodiment of the present application. The apparatus 1900 in the embodiment of the present application may be the receiving end in any of the foregoing method embodiments, or may be one or more chips in the receiving end. The apparatus 1900 may be used to perform part or all of the functions of the receiving end in the foregoing method embodiments.

The apparatus 1900 may be used to perform part or all of the functions of the receiving end in any of the foregoing method embodiments. The device 1900 may include a processor 1910, a baseband circuit 1930, a radio frequency circuit 1940, and an antenna 1950. Optionally, the device 1900 may also include a memory 1920. The various components of the device 1900 are coupled together via a bus 1960. In addition to the data bus, the bus system 1960 also includes a power bus, a control bus, and a status signal bus. However, for clear description, various buses are marked as the bus system 1960 in the figure.

The processor 1910 may be used to control the receiving end, to perform the processing performed by the receiving end in the above-mentioned embodiment, and to perform the processing procedures related to the sending end in the above-mentioned method embodiments and/or other technologies used in the technology described in this application. During the process, the operating system can also be run, which is responsible for managing the bus and can execute programs or instructions stored in the memory.

The baseband circuit 1930, the radio frequency circuit 1940, and the antenna 1950 can be used to support sending and receiving information between the receiving end and the transmitting end involved in the foregoing embodiment, so as to support wireless communication between the receiving end and the transmitting end. In an example, the signal sent from the transmitting end is received by the antenna 1950, filtered, amplified, down-converted, and digitized by the radio frequency circuit, and then decoded by the baseband circuit, and then decapsulated data according to the protocol. 1910 performs processing to restore the service data and signaling information sent by the sender. For example, the receiver decodes and decapsulates the received PPDU to obtain A-MPDU, and then analyzes the processor to obtain the retransmitted MPDU or the first transmitted MPDU MPDU; In another example, the confirmation feedback information of the receiving end can be processed by the processor 1910, and the baseband circuit 1930 performs baseband processing such as protocol packaging and encoding, and the radio frequency circuit 1940 performs analog conversion, filtering, amplification, and upconversion After processing, it is transmitted via the antenna 1950. The memory 1920 can be used to store the program code and data of the sending end, and the memory 1920 can be a storage module. It can be understood that the baseband circuit 1930, the radio frequency circuit 1940, and the antenna 1950 may also be used to support the receiving end to communicate with other network entities.

It is understandable that Figure 19 only shows a simplified design of the receiving end. For example, in practical applications, the receiving end may include any number of transmitters, receivers, processors, memories, etc., and all receiving ends that can implement the present invention are within the protection scope of the present invention. The processors involved in the foregoing apparatus 1800 and apparatus 1900 may be general-purpose processors, such as general-purpose central processing units (CPU), network processors (Network Processor, NP for short), microprocessors, etc., or may be application-specific integrated circuits ( application-specific integrated circBIt, ASIC for short), or one or more integrated circuits used to control the execution of the program of this application. It may also be a digital signal processor (Digital Signal Processor, DSP for short), a Field-Programmable Gate Array (FPGA for short) or other programmable logic devices, discrete gates or transistor logic devices, or discrete hardware components. The controller/processor may also be a combination of computing functions, for example, a combination of one or more microprocessors, a combination of a DSP and a microprocessor, and so on. The processor usually executes logic and arithmetic operations based on program instructions stored in the memory.

The storage involved in the foregoing apparatus 1800 and apparatus 1900 may also store an operating system and other application programs. Specifically, the program may include program code, and the program code includes computer operation instructions. More specifically, the aforementioned memory may be a read-only memory (read-only memory, ROM for short), other types of static storage devices that can store static information and instructions, random access memory (RAM for short), and storage Other types of dynamic storage devices for information and instructions, disk storage, etc. The memory can be a combination of the storage types described above. In addition, the aforementioned computer-readable storage medium/memory may be in the processor, or external to the processor, or distributed on multiple entities including the processor or processing circuit. The aforementioned computer-readable storage medium/memory may be embodied in a computer program product. For example, the computer program product may include a computer-readable medium in packaging materials.

The embodiment of the present application also provides a chip system, the chip system includes a processor, which is used to support the sending end or the second receiving end to realize the functions involved in any of the above embodiments, for example, generating or processing the functions mentioned in the above method. The data and/or information involved. In a possible design, the chip system may further include a memory, and the memory is used for necessary program instructions and data at the sending end or the receiving end. The chip system can be composed of chips, or include chips and other discrete devices.

The embodiments of the present application also provide a processor, which is configured to be coupled with a memory and used to execute methods and functions related to the sending end or the receiving end in any of the foregoing embodiments.

The embodiments of the present application also provide a computer program product containing instructions, which when running on a computer, causes the computer to execute the methods and functions related to the sending end or the receiving end in any of the foregoing embodiments.

The embodiments of the present application also provide a device for executing the methods and functions related to the receiving end or the transmitting end in any of the foregoing embodiments.

An embodiment of the present application also provides a wireless communication system, which includes at least one transmitting end and at least one receiving end involved in any of the foregoing embodiments.

In the several embodiments provided in this application, it should be understood that the disclosed system, device, and method may be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components may be combined or It can be integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms. As another possible product form, the data transmission device can also be implemented using the following: Field-Programmable Gate Array (FPGA), Programmable Logic Device (PLD), controller, State machines, gate logic, discrete hardware components, etc., any other suitable circuits, or any combination of circuits capable of performing the various functions described throughout this application.

In the above-mentioned embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented by software, it can be implemented in the form of a computer program product in whole or in part. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, all or part of the processes or functions described in this application are generated. The computer may be a general-purpose computer, a dedicated computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center. Transmission to another website, computer, server or data center via wired (such as coaxial cable, optical fiber or digital subscriber line) or wireless (such as infrared, wireless or microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or data center integrated with one or more available media. The usable medium may be a magnetic medium, (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk).

Claims

A method for sending retransmitted data, applied to a sending end, and characterized in that it includes:

Send a first aggregated media intervention control protocol data unit A-MPDU, the first A-MPDU includes M A-MPDU subframes and M tail bit parts, one tail bit part and one A-MPDU subframe For frame correspondence, the M is greater than or equal to 1;

Determine the N MPDUs that need to be retransmitted in the first A-MPDU, and the N MPDUs are respectively included in the N A-MPDU subframes of the first A-MPDU; the N is greater than or equal to 1, so Said M is greater than or equal to N;

Sending a second A-MPDU, the second A-MPDU including the N A-MPDU subframes and N tail bit parts corresponding to the N A-MPDU subframes;

Wherein: a tail bit part includes at least 6 bits, and the at least 6 bits are a preset value.
The method according to claim 1, wherein the N A-MPDU subframes in the first A-MPDU correspond to the first-transmission coded bits obtained by BCC encoding by using the first-transmission coding parameter encoding; the second The N A-MPDU subframes in the A-MPDU correspond to the retransmission coded bits obtained by BCC coding using retransmission coding parameter coding;

The retransmission coding parameter is the same as the first transmission coding parameter or has a preset relationship.
The method according to claim 1, wherein one of the tail bits is located at the last at least 6 bits in the one A-MPDU subframe.
The method according to any one of claims 1 to 3, wherein one of the A-MPDU subframes includes a padding field, and if the padding field is greater than 0 bytes and less than 4 bytes, the tail bit Partly located in the last 6 bits of the padding field; or,

If the padding field included in the A-MPDU subframe is 0 bytes, the method further includes: padding an additional 4 bytes in the padding field of the A-MPDU subframe, and the tail bit part is located in the additional padding. At least 6 bits of the last 4 bytes.
The method according to claim 1 or 2, wherein one of the tail bits is located at least 6 bits filled after the one A-MPDU subframe.
The method according to any one of claims 1 to 5, wherein the tail bit part includes 6 bits, and the value of the 6 bits is 000000.
The method according to any one of claims 1 to 6, wherein the second A-MPDU subframe is carried in a second physical layer protocol data unit PPDU, and the second PPDU includes a physical layer preamble, The physical layer preamble includes one or more of the following:

A retransmission indication, used to indicate whether the second PPDU includes a retransmitted MPDU, the retransmission indication takes a first value, and is used to indicate that the second PPDU includes a retransmitted MPDU;

Modulation and coding scheme indication, if the modulation and coding scheme indication is a special value, the special value is used to indicate that the second PPDU only includes retransmitted MPDUs;

The retransmission length indicator is used to indicate the total length or total duration of the N A-MPDU subframes included in the second PPDU;

The tail bit part position indicator is used to indicate the position of the tail bit part corresponding to the last A-MPDU subframe in the N A-MPDU subframes.
A method for receiving retransmitted data, applied to a receiving end, and characterized in that it includes:

Receive a first A-MPDU, where the first A-MPDU includes M A-MPDU subframes and M tail bit parts, one tail bit part corresponds to one A-MPDU subframe, and the M is greater than Equal to 1

Receive a second A-MPDU, where the second A-MPDU includes the N A-MPDU subframes and N tail bit parts corresponding to the N A-MPDU subframes; one tail bit part Includes at least 6 bits, and the at least 6 bits are a preset value; the N A-MPDU subframes include N MPDUs that need to be retransmitted in the first A-MPDU; the N is greater than or equal to 1, the M is greater than or equal to N;

The LLR of the first transmitted coded bit corresponding to the N A-MPDU subframes in the first A-MPDU and the LLR of the retransmitted coded bit corresponding to the N A-MPDU subframes in the second A-MPDU Perform combined decoding or joint decoding to obtain the N A-MPDU subframes.
According to the method of claim 8, the N A-MPDU subframes in the first A-MPDU correspond to the first-pass coded bits obtained by BCC coding by using the first-pass coding parameter encoding; the second A-MPDU The N A-MPDU subframes in the MPDU correspond to the retransmission coded bits obtained by performing BCC coding using retransmission coding parameter coding;

Wherein, the retransmission coding parameter is the same as the first transmission coding parameter or has a preset relationship.
The method according to claim 8, wherein one of the tail bits is located at least 6 bits in the last of the one A-MPDU subframe.
The method according to any one of claims 8 to 10, wherein one of the A-MPDU subframes includes a padding field, and if the padding field is greater than 0 bytes and less than 4 bytes, the tail bit Partly located in the last 6 bits of the padding field; or,

If the padding field included in the A-MPDU subframe is 0 bytes, the method further includes: padding an additional 4 bytes in the padding field of the A-MPDU subframe, and the tail bit part is located in the additional padding. At least 6 bits of the last 4 bytes.
The method according to claim 8 or 9, wherein one of the tail bits is located at least 6 bits filled after the one A-MPDU subframe.
The method according to any one of claims 8 to 12, wherein the tail bit part includes 6 bits, and the value of the 6 bits is 000000.
The method according to any one of claims 8 to 13, wherein the second A-MPDU subframe is carried in a second PPDU, and the second PPDU includes a physical layer preamble, and the physical layer preamble Including one or more of the following:

A retransmission indication, used to indicate whether the second PPDU includes a retransmitted MPDU, the retransmission indication takes a first value, and is used to indicate that the PPDU includes a retransmitted MPDU;

Modulation and coding scheme indication, if the modulation and coding scheme indication is a special value, the special value is used to indicate that the second PPDU only includes retransmitted MPDUs;

The retransmission length indicator is used to indicate the total length of the N A-MPDU subframes included in the second PPDU;

The tail bit part position indicator is used to indicate the position of the tail bit part corresponding to the last A-MPDU subframe in the N A-MPDU subframes.
A sending device for retransmission of data includes:

A sending module, configured to send a first A-MPDU, where the first A-MPDU includes M A-MPDU subframes and M tail bit parts, and one tail bit part corresponds to one A-MPDU subframe , The M is greater than or equal to 1;

A processing module, configured to determine N MPDUs that need to be retransmitted in the first A-MPDU, where the N MPDUs are respectively included in N A-MPDU subframes of the first A-MPDU; the N Greater than or equal to 1, the M is greater than or equal to N;

The sending module is further configured to send a second A-MPDU, the second A-MPDU including the N A-MPDU subframes and N tail bits corresponding to the N A-MPDU subframes section;

Wherein: a tail bit part includes at least 6 bits, and the at least 6 bits are a preset value.
The apparatus according to claim 15, wherein the N A-MPDU subframes in the first A-MPDU correspond to the first-transmission coded bits obtained by using the first-transmission coding parameter encoding for BCC encoding; the second The N A-MPDU subframes in the A-MPDU correspond to the retransmission coded bits obtained by BCC coding using retransmission coding parameter coding;

The retransmission coding parameter is the same as the first transmission coding parameter or has a preset relationship.
The apparatus according to claim 15 or 16, wherein one of the tail bits is located at the last at least 6 bits in the one A-MPDU subframe.
The apparatus according to any one of claims 15 to 17, wherein one of the A-MPDU subframes includes a padding field, and if the padding field is greater than 0 bytes and less than 4 bytes, the tail bit Partly located in the last 6 bits of the padding field; or,

If the padding field included in the A-MPDU subframe is 0 bytes, the apparatus further includes: padding an additional 4 bytes in the padding field of the A-MPDU subframe, and the tail bit part is located in the additional padding. At least 6 bits of the last 4 bytes.
The apparatus according to claim 15 or 16, wherein one of the tail bits is located at least 6 bits filled after the one A-MPDU subframe.
The apparatus according to any one of claims 15 to 19, wherein the tail bit part includes 6 bits, and the value of the 6 bits is 000000.
The apparatus according to any one of claims 15 to 20, wherein the second A-MPDU subframe is carried in a second PPDU, and the second PPDU includes a physical layer preamble, and the physical layer preamble Including one or more of the following:

A retransmission indication, used to indicate whether the second PPDU includes a retransmitted MPDU, the retransmission indication takes a first value, and is used to indicate that the second PPDU includes a retransmitted MPDU;

Modulation and coding scheme indication, if the modulation and coding scheme indication is a special value, the special value is used to indicate that the second PPDU only includes retransmitted MPDUs;

The retransmission length indicator is used to indicate the total length or total duration of the N A-MPDU subframes included in the second PPDU;

The tail bit part position indicator is used to indicate the position of the tail bit part corresponding to the last A-MPDU subframe in the N A-MPDU subframes.
A receiving device for retransmission of data, characterized in that it comprises:

The receiving module is configured to receive a first A-MPDU, where the first A-MPDU includes M A-MPDU subframes and M tail bit parts, and one tail bit part corresponds to one A-MPDU subframe , The M is greater than or equal to 1;

The receiving module is further configured to receive a second A-MPDU, where the second A-MPDU includes the N A-MPDU subframes and N tail bits corresponding to the N A-MPDU subframes Part; one of the tail bits includes at least 6 bits, and the at least 6 bits are preset values; the N A-MPDU subframes include the N MPDUs that need to be retransmitted in the first A-MPDU; The N is greater than or equal to 1, and the M is greater than or equal to N;

The processing module is configured to re-transmit the LLR corresponding to the N A-MPDU subframes in the first A-MPDU and the N A-MPDU subframes corresponding to the second A-MPDU The LLRs transmitting the coded bits are combined or jointly decoded to obtain the N A-MPDU subframes.
The apparatus according to claim 22, wherein the N A-MPDU subframes in the first A-MPDU correspond to the first-pass coded bits obtained by BCC coding by using the first-pass coding parameter encoding; the second A-MPDU The N A-MPDU subframes in the MPDU correspond to the retransmission coded bits obtained by performing BCC coding using retransmission coding parameter coding;

Wherein, the retransmission coding parameter is the same as the first transmission coding parameter or has a preset relationship.
The apparatus according to claim 22 or 23, wherein one of the tail bits part is located at the last at least 6 bits in the one A-MPDU subframe.
The apparatus according to any one of claims 22 to 24, wherein one of the A-MPDU subframes includes a padding field, and if the padding field is greater than 0 bytes and less than 4 bytes, the tail bit Partly located in the last 6 bits of the padding field; or,

If the padding field included in the A-MPDU subframe is 0 bytes, the apparatus further includes: padding an additional 4 bytes in the padding field of the A-MPDU subframe, and the tail bit part is located in the additional padding. At least 6 bits of the last 4 bytes.
The apparatus according to claim 22 or 23, wherein one of the tail bits is located at least 6 bits filled after the one A-MPDU subframe.
The apparatus according to any one of claims 22 to 26, wherein the tail bit part includes 6 bits, and the value of the 6 bits is 000000.
The apparatus according to any one of claims 22 to 27, wherein the second A-MPDU subframe is carried in a second PPDU, and the second PPDU includes a physical layer preamble, and the physical layer preamble Including one or more of the following:

A retransmission indication is used to indicate whether the second PPDU includes a retransmitted MPDU, and the retransmission indication takes a first value and is used to indicate that the PPDU includes a retransmitted MPDU;

Modulation and coding scheme indication, if the modulation and coding scheme indication is a special value, the special value is used to indicate that the second PPDU only includes retransmitted MPDUs;

The retransmission length indicator is used to indicate the total length of the N A-MPDU subframes included in the second PPDU;

The tail bit part position indicator is used to indicate the position of the tail bit part corresponding to the last A-MPDU subframe in the N A-MPDU subframes.
A sending device for a sending end, comprising: a memory and a processor, the memory is coupled to the processor, the memory is used to store a computer program, the computer program includes program instructions; the processor is used to call the program instructions to implement The method according to any one of claims 1 to 7.
A receiving device for the receiving end, comprising: a memory and a processor, the memory is coupled to the processor, the memory is used for storing a computer program, the computer program includes program instructions; the processor is used for calling The program instructions implement the data transmission method according to any one of claims 8 to 14.
A computer-readable storage medium, the computer-readable storage medium stores a computer program, the computer program contains at least one piece of code, the at least one piece of code is executed by a computer to control the computer to execute claims 1 to 14 The method of any one of.
A computer program, when the computer program is executed by a computer, is used to execute the data transmission method according to any one of claims 1 to 14.